Maureen Grey stood in the middle of the yard beneath the flats where she had lived her whole life. Just another block of 1960s flats, a community of sorts, where she had friends and neighbours, and until recently she would have said she was happy.

The one unusual thing about these flats was the faded yellow painted square near the bins. Long ago, for reasons most people had forgotten, the square had been drawn and the words “Free Parking for Aliens” painted inside. New residents assumed it was a joke.

It wasn’t.

She smiled as a wind came from nowhere, ruffling her hair and making her instinctively reach to hold her skirt down. With the wind came a noise that she hadn’t heard for a while, but which she had come to associate with things being ok. Or if they weren’t, with help coming that would make them ok.

The alien ship disguised as an old fashioned 1950s police telephone box solidified and a few seconds later the door opened. Maureen gave a cry of delight as she hugged her old friend, Jackie Tyler. Or… she ALWAYS forgot her married name. It sounded foreign. It would do of course. It was BEYOND foreign. It was ALIEN.

Maureen was one of the few people who knew that Jackie didn’t marry an Australian and move to Sydney, but married an alien and moved to the twenty-third century.

“It’s lovely to see you,” she said. “Oh, when’s the baby due?”

“Late December,” Jackie answered. Maureen looked puzzled. It was September and Jackie looked ready to drop any moment. In another four months she would need a counter-balance just to stand.

“Don’t worry about it,” she told her old friend. “Maureen, you remember my Christopher, don’t you?”

“Of course I do,” Maureen answered. “He’s still drop dead gorgeous. And still wearing a suit. People will think he’s from the DSS.”

Jackie laughed. Christopher shook hands politely with Maureen and then took his wife’s hand as they walked to the entrance to Buckland House on the Powell Estate. The lift was out of order. Christopher smiled and reached into his pocket for his sonic screwdriver.

“His dad taught him that trick,” Jackie said with a grin as the lift arrived.

“I hope he taught him a few more tricks,” Maureen answered. “No offence, Christopher, but I was hoping The Doctor would come. I think we NEED his kind of expertise.”

“He’s not well,” Jackie told her.

Maureen looked at her in surprise and concern.

“I didn’t think The Doctor could GET ill. The world without him fit and well… Doesn’t bear thinking about.”

“I thought so, too,” Jackie answered. “But he’s getting better. And in the meantime, the twins are nearly as good as he is, and so is Christopher. So don’t worry. The problems you have here. We can help.”

“I’ll do my best,” Christopher promised.

“Your dad thinks you’re capable,” Jackie assured him.

“He’s not exactly an impartial judge,” Christopher admitted. “But tell me what the problem is, Maureen, and I’ll do my best.”

Maureen looked at him. She’d known him, on and off, for about six years. Ever since Jackie started ‘seeing’ him. She knew he was different. He was The Doctor’s son, and that was the first strange thing about him, since he looked nearly the same age as his father. And she knew that was because they were both aliens.

He didn’t look anything like his father. But there was something in his face that made her trust him.

She brought them into the flat. It was exactly the same size and shape as Jackie’s old home, the same as all the flats in the block. Jackie and Maureen had both brought up a child on their own in exactly the same living space. The only difference between them was that Jackie was a widow and Maureen an abandoned wife, Mark’s father having run out on them before he was even born. Mark was a young man now and the flat was tidy and homely. The walls were decorated with framed drawings. Mark was an art student and his mother was proud to display his work. They were detailed pencil drawings of the flats and the streets around them. Urban landscapes. The biggest and most detailed one was of the yard below with the TARDIS parked by the bins.

“The one Mark drew when he was a little lad is still pinned up in the TARDIS,” Jackie said with a smile as Maureen gave them coffee and biscuits and they tried to avoid the question that had to be asked. WHY had she asked them to come so urgently.

“Yes,” Maureen said. “He has a lot more of the TARDIS on the walls in his room. The Doctor has always been a hero to him.”

Jackie and Maureen exchanged glances as they remembered the reason for that hero worship. Mark had been snatched by a paedophile and it was The Doctor who had tracked him down and rescued him while the police were blundering about wrong-footed and the neighbourhood had been on a foolish witch-hunt against The Doctor himself.

Water under the bridge a long time ago.

For a few minutes more they avoided that question. Then finally Maureen put down her cup and turned to Christopher.

“I hope you ARE as good as your dad,” she said. “Because we need somebody who is. We’re in a lot of trouble here.”

“What sort of trouble?” Christopher asked.

“People dying strangely,” she answered. “Old people. Something is killing them. I know… I know what you’re thinking. Old people ALWAYS die. But not like this. Not even in really cold winters. And this is only the end of summer, yet.”

“All right,” Christopher said to her gently. “Take your time and start from the beginning.”

“It began two weeks ago. There were five deaths in one week. Mr Lyndsay from 17b, Mrs Marton, Miss Perry and Miss Dryden, the two daft ones that used to keep themselves to themselves. Both of them together. The milkman called the police when he found the milk still in the cubby by the door from the day before. And then, this week, Monday, there were FIVE all in one night. There were ambulances here all morning. And the police. They questioned the Meals on Wheels man, because somebody accused him of poisoning them. But there was no sign of poison and anyway, Miss Penny and Miss Dryden and Mr Crowther never took the meals. They were all too proud to accept what they called charity. And I heard somebody say that the coroner said that they all died of brain an.. anuer… Oh… what’s the word?”

“Aneurysm,” Christopher said. “Yes, that’s… well its something elderly Humans DO die of. Young Humans, too, for that matter. But ALL of them? If that WAS the case. ‘Somebody said the coroner said…’ is a bit vague. Even so, you’re quite right. Something strange is going on. Nine people dead in two weeks?”

“Fifteen,” Maureen corrected him. “It’s like it spread. It happened in the maisonettes over the shops and in the old terraced streets behind the flats where a lot of old folk have lived since before the flats were even here. It’s really HORRIBLE. And… and I’m just glad my mum and dad are gone. If it happened to them…”

Jackie had been thinking the same thing. Her parents were long gone and Pete’s mum had died before she married Christopher. She had nobody close to her. But even so, HORRIBLE was the word. She knew most of the people Maureen had named, by sight at least. They were the people who made up the backbone of the community around here. The ones who were seen every Tuesday with their shopping trolleys, getting on the Age Concern minibus to ASDA for their ‘messages’ or the community centre minibus for bingo or bowls. They were the ones who had been there always. They had been the parents of HER generation. Most of their children had bettered themselves and moved away. It was only the ones like her and Maureen, the single mums, who had stayed around. Of course they were in their forties now and a whole new generation of single mums were pushing prams now. But the old people were still there.

Or they WERE.

She looked at Christopher. He was thinking. He had a look about him when he was thinking. She’d seen him many times, sitting in parliament, on the Cabinet bench, listening as some Bill or other was read. And he would be thinking deeply. And when the time was right he would stand and speak and everyone else would sit very still and quiet, and listen to him.

He didn’t stand this time. He wasn’t in parliament now. But he did sit up very straight and he took Maureen’s hand gently.

“I believe something sinister is going on,” he said. “But, my dear lady, what did you think I… or my father for that matter…. would be able to do about it?”

“I don’t really know,” she answered him. “I just felt… if anyone CAN help us…” Her mouth trembled with emotion as she spoke. “Do you mean you WON’T help?”

“Not at all,” Christopher assured her. “I just don’t quite know where to begin and I really don’t think my father would know, either. But neither of us would turn our backs. I’m just wondering…”

His train of thought was halted by the sound of the front door banging open. They all turned to look as Mark Grey ran in, pulling a motor-cycle helmet off his head. He stopped as he saw Christopher sitting with his mother.

“Oh….” He said, slightly disappointed. “I saw the TARDIS. And I thought… hoped…”

“My father sends his regards,” Christopher told him.

“We need him,” Mark insisted. “It’s happened again. At the sheltered housing project. The police are there now.”

“Oh, my God!” Jackie murmured. “That’s the place where Pete’s mum lived.”

“Show me,” Christopher said to Mark.

“I’m on the bike,” he said. “I’ve got a spare helmet.”

“Yes, all right.” Christopher turned to Jackie and kissed her fondly. “You and Maureen take care of each other. I’ll be back as soon as I can.”

The two women stepped out onto the balcony, curious to see if Christopher knew how to ride pillion on a motorbike. He certainly wasn’t DRESSED for it in his smart suit. But he put on the helmet and sat behind Mark. He hung on as they rode past the TARDIS and out of the yard. Maureen and Jackie looked at each other and sighed and turned back into the flat.

Christopher had NEVER ridden a motorbike before. But he remembered riding beside his father on a two man anti-grav-bike across the Red Desert of Gallifrey. His father loved to push the bike to its limits as they sped across the red sand, some ten or fifteen feet above it, or going low and leaving tracks from the anti-grav field in the untouched sand. He had never inherited the taste for speed, though. He enjoyed that sport because he and his father did it together and he loved anything they did as father and son.

He would probably never learn to love motorbikes. Especially in London traffic. The fifteen minute journey was at least thirteen minutes too long for him.

When he reached the sheltered housing project, though, he forgot all about his own discomfort. He took in the ambulances and the police and the people, mostly elderly, standing in the paved courtyard crying and berating the project staff for not doing enough to protect them.

There was a small contingent of people in uniforms hovering around one door. Christopher moved towards them, noting that there were police, ambulance and a man from the RSPCA with a pair of wire cages for transporting small animals.

“What’s the problem?” he asked with an air of somebody who would have the answer no matter what the question was.

“The door is locked and bolted from the inside,” said the policeman. “The supervisor says Mr Glynn had a whole set of non-regulation locks put on. He was convinced that he would be robbed by the housing project staff with their pass keys.”

“He’s definitely a victim?” Christopher asked. But he knew the answer to the question without asking. There was a feeling about this little house. A feeling that caught him in his soul. Death lay behind the door.

Death and a lot of cats. They could hear them meowing loudly.

“He has about ten of them, apparently,” said the man from the RSPCA, holding up the cages.

“Very well, stand back.” Christopher extracted his sonic screwdriver from his pocket. He set it to one of its easiest functions. He was by no means an expert on all of the thousands of settings, but the one that unlocked ordinary locks made by Human locksmiths was easy.

In the back of the minds of the policeman, paramedic and RSCPA officer there was a nagging question – why is this stranger taking over from us? But none of them had the strength of mind to bring the question forward and ask it. They followed him into the corridor that led to the kitchen, living room, bathroom and one bedroom of this sheltered home for a single elderly tenant.

It smelt strange. It took Christopher a few moments to work out the overlaid smells. Cats. The furry organic smell was definitely cats. He had never owned a cat but he had got used to the smell through visiting his constituents who owned pets. The other strong smells were familiar, too. Tea and pipe tobacco. Tea WAS a smell he knew of old. English tea was a drink unique to the House of Lœngbærrow on Gallifrey. His Human mother always drank tea. So did his Time Lord father and grandfather, both of whom picked up the habit from their wives. Tobacco, he also remembered. His grandfather was partial to cigars and his father used to smoke a pipe. Of course the tea they imported was tannin free and the tobacco available on Gallifrey was non-carcinogenic. But the two smells, together, were ones that gave him a nostalgic twist in his stomach for an easier, more carefree time that was long gone.

The other smell had nothing to do with being carefree. It was the smell of death. He remembered bitterly the first time he had known death. He came from a people who lived long lives and, barring accidents, rarely died. But when he was still young by the measurements of his long-lived race, his Human mother had died. He and his father had sat with her in the last minutes. He had kissed her cheek and listened to her tell him how much she loved him. Then he had watched his father gather her in his arms and kiss her as he always kissed her. For a brief moment they had both seen her as she was when he was a child, a pretty woman with long dark hair and black-brown eyes that were pools of love. Then he watched his father lay her slowly back down on the pillow. He smoothed her white hair and caressed her lined face. But she no longer felt his touch. Her soul was gone from her body. His father had cried. Christopher, a scholar of the Prydonian Academy, a place where he had learnt to hide that Human part of him, didn’t cry. He held his grief in. But he had grieved just as strongly as the two of them kept a quiet vigil through the night, a last few hours with her. At dawn his father had roused the servants and had them make the necessary preparations for the House of Lœngbærrow to be a house of mourning.

Yes, that same smell of death was on this little home. And the dead man was easily found. He was in his bed. He was very clearly dead. He was lying in a twisted heap of blankets and pillows and his hand was on a gun. A very old fashioned gun, Christopher thought, though he was far from an expert on such things. But it looked like the sort used in the war that that been fought when this old man was a child. How he came to have it, and how it was still in working order he didn’t know. But what he did know was that the old man had shot at something with the gun. There was blood on the floor.

Not Human blood. Neither the policeman nor the paramedic thought it was blood. They ignored it completely as they paid attention to the corpse and the RSPCA man rounded up the cats.

Christopher watched as the paramedic reached to close the old man’s staring eyes, and again remembered back to when his father had done the same to his mother. But the policeman stopped him. He said this looked like a crime scene, not like the others. He said he would have to bring in CID, and in the meantime they shouldn’t touch anything.

Christopher ignored that injunction. He went to the bathroom and found a small plastic jar with a doctor’s label on and then to the kitchen where he found a small spoon. He gathered a sample of the yellow-brown substance on the bedroom floor that had the smell of blood, but not the sharp iron smell of red Human blood. There was a large pool of it there. But there were smaller droplets leading to the door. In the hallway some of them had been trodden as the four of them came in, but they were the pattern of somebody or some THING that was wounded, moving towards the door.

And there was something nobody had seen because they headed straight for the bedroom.

A handprint. Made by something with only two long fingers and a thumb.

He took out his mobile phone and photographed the print several times. He photographed the locks that he had opened with the sonic screwdriver. One was the Yale type that snapped shut, but the others were all five lever mortices that needed a key. On the hinge side of the door were key-operated bolts that shot into the doorframe and held it secure. They only worked from the inside unless you had a sonic screwdriver.

So HOW did the creature, whatever it was, get OUT?

Of course there were such things as teleports and transmats. But if the creature had such technology, WHY did it go to the door at all?

He opened the door and stepped out. Yes, there were drops of the non-Human blood there on the tarmac path, too. He followed them down the path and noted that they continued along the pavement for about twenty yards, then stopped. There was a larger pool as if the creature had stood there for a little longer.

It had got into a vehicle, of course, Christopher realised. The trail was cold. But he had something to be going on with.

“Christopher?” he turned and saw Mark standing there, his helmet in his hand. “Did you find something?”

“Yes, I did,” he answered. “Though I didn’t get a chance to look at the body. There were too many people about. Do you know which hospital they are being taken to?”

“Albion Hospital,” Mark answered. “It’s not far away. But they won’t let you into the morgue, surely?”

Christopher paused in thought. In the 23rd century they would let him in just about anywhere. He was a cabinet minister. The hospital would roll out the red carpet for him. Here in the 21st century he was a nobody. But he was a nobody with all the bearing of his aristocratic Gallifreyan blood, a sonic screwdriver and a wallet containing psychic paper. Yes, he thought they would let him in.

“Tell you what,” he said. “Drive me back to flats and we’ll go in the TARDIS.”

He phoned Jackie to let her know his plans. She and Maureen waved from the balcony as he opened the TARDIS door. He waved back.

“You’ve been in the TARDIS before, haven’t you?” he asked Mark as he closed the door and went to the console.

“Yes,” he answered. “When I was a kid, The Doctor used to let some of us come in and look around as long as we were quiet and didn’t touch anything. We didn’t DARE touch anything. It just freaked us out. But we loved it. And he was great. He used to answer all our dumb questions about him being an alien, and the planet he came from and other cool places. It was strange. The adults, our parents, all knew this was a spaceship and that it was like this inside and able to fly. But they somehow blocked it out of their heads. They just had this kind of idea we were playing somewhere safe and that’s all they needed to know. It was the same as the thing with the alien spaceship that landed in the Thames. We all saw it on the news. Big Ben had scaffolding on it for a year. Downing Street blew up. But the adults all sort of forgot that it was anything unusual.”

“Adult humans have very complicated psychology,” Christopher said,. “That’s how my father explains it anyway.”

“I’m nineteen,” Mark went on. “More or less an adult. I can ride a bike, vote, have a drink, all of that. But I still feel like…” He watched as Christopher operated the console. The thing he knew was called a time rotor began to move up and down and he felt a thrill in his heart as he felt the faint vibration and a very slight feeling of movement that told him they were in flight. “I’m nineteen, a teenager, and I’m flying in a space ship. I don’t think I’ll ever become one of those adults that doesn’t see these things.”

“I’m sorry this is not a more exciting trip for your first outing. We’re not going to the moon or anything. Just a few miles to the hospital.”

“That’s ok. I’m still travelling in a space ship, The Doctor’s space ship.”

Christopher looked up from the console. “You know, I’ve been using it more than him lately. I almost think of it as MINE. Still…” He moved around from the drive to another section of the console. He took out his mobile phone and interfaced it with the computer. Mark saw the pictures of the alien handprint appear on the viewscreen. He watched as Christopher put some of the blood into a receptacle for analysis.

“I’m hoping it can tell us what we’re up against. The TARDIS has a huge database of species that my people have recorded for millennia. My father added hundreds of thousands to it himself. The print plus the blood sample with its DNA in it should come up with something.”

To his disappointment it didn’t come up with anything immediately.

“It’s a very BIG database,” he added. “Here we are. We’ve arrived.”

The two women drank coffee and talked about the possibility of doing some baby clothes shopping before Jackie went back to the 23rd century. They talked about Jackie’s hopes for her new baby, and how lucky she was to have a chance at her age to have another child. They talked about what was happening on the soaps which Jackie hadn’t seen in about two years. Then their conversation drifted back to the main one. The deaths all around them.

“I just hope your Christopher can find something out. It’s been AWFUL. We just wonder who’s next.”

“And WHY old people?” Jackie mused. “They must be cowards, whoever it is doing it. Picking on the most vulnerable. When Christopher gets them… ”

When? If? And if he did, what would he do? He wasn’t his dad. And even his dad drew a line at killing people. Neither of them believed violence solved anything. What WOULD he do?

“I was just thinking,” Maureen said. “The people in your old flat. They’ve got an elderly person. Their grandfather, I think it is. Do you think we ought to see if he’s all right?”

“Would they think we’re being nosy?” Jackie thought about it for a bit. “It’s MY flat, after all. I’m entitled to call and check if they’re keeping the place decent.”

She had bought the flat ages ago. When The Doctor and Rose got engaged she had been paid a huge sum of money. It was a tradition of The Doctor’s world and he wouldn’t take no for an answer. So she bought her flat and had it redecorated and made really nice. When she left it, finally, Christopher arranged for it to be rented out through a letting agency. The money went into a bank account for her. Two hundred years in the future Jackie was a very well off and independent woman in her own right from the interest accrued.

They left a note in case they were longer than they expected and went to see if the lift was still working.

The TARDIS materialised in a walk in cupboard. It was full of white lab coats.

“That’s convenient,” Mark said as he reached for one of the coats.

“Are you sure you want to come with me?” Christopher asked as he, too, put on a lab coat. “We’re going to a mortuary, to look at bodies. There may even be autopsies in progress.”

“I’ll handle it,” he answered. “What about you? Aren’t you a politician? That doesn’t exactly qualify you for looking at bodies, either.”

“I was killed once,” Christopher said cryptically. “I can handle anything after that.”

He said so, because he didn’t want to look as if he wasn’t capable. But in his hearts he wasn’t entirely sure. He was a long way out of his depth already. He had no experience of this sort of thing. His father would be better equipped. He had a wealth of medical experience, and had seen a lot more dead people than he had.

He was following his father in one respect, though.

He was ‘winging it.’

There WAS an autopsy going on as they entered the mortuary. The medical examiner looked around with blood dripping from his rubber gloves and looked at the two visitors.

“Are you the people we’re expecting from Torchwood?” he asked.

“Yes,” Christopher answered and held up his psychic paper to prove it. He wasn’t even entirely sure what Torchwood WAS. It was a word he had heard his father use in a tone that suggested he considered them rank amateurs. But it seemed a useful cover right now. “I take it you believe something here requires our attention?”

“Obviously, that’s why I contacted you,” the Medical Examiner answered. “I’m busy here. But if you want to start examining one of the other suspicious cases, then those three there have just come in.”

Christopher was happy to turn away from the table where the body of an elderly man had been opened up from throat to abdomen. The intact bodies were far easier to stomach. He took out his sonic screwdriver once more, wondering if there was anything it couldn’t be useful for. He set it to medical analysis mode. He had never used that setting before. He looked it up while the TARDIS was in transit. But to his surprise and satisfaction it worked as a handheld scanner as he held it along the body.

He would have to interface it with the TARDIS to get any meaningful readout. But even so he was fairly sure there was something anomalous in the scan. He tried the two other bodies that were brought in this morning from the sheltered housing project and the same anomaly was present. He looked around and then crossed the room. He tried the analysis on the body of a young man whose toe tag said he died of gun shot wounds. Yes, there was definitely something that Torchwood would be interested in. And something HE was interested in, if he could interpret the findings.

“Have you seen this?” asked the Medical Examiner, calling him back over to the three bodies lined up ready to be autopsied. “I found this same mark on all of the victims. That’s how I knew there was something connecting them, and how I knew it was a matter for you people.”

Christopher looked at the mark on the neck of the victim. Just below the hairline there was a circular indentation in the flesh, and a distinct puncture in the middle that broke the skin and caused blood to flow. He reached for his mobile phone again and took several pictures to go with the ones he had taken of the handprint.

“I’ve got enough to be going on with,” he said to the Medical Examiner at last. “But Torchwood will be wanting copies of the full autopsy results. You know where to send them.”

He turned and nodded to Mark and they left the mortuary together. As they made their way down the basement corridor two people passed them going in the other direction. They both wore name tags identifying them as Torchwood personnel.

“Let’s walk very quickly,” Christopher said. “But not so fast to make us seem suspicious.”

The door to Jackie’s old flat was opened by a young woman with long dark hair and a pale complexion that contrasted with blood red lips. The Bride of Dracula effect was increased when she spoke with an Eastern European accent.

“I am Claudia Dragos,” she said. “My sisters are out at present, but you are welcome to come in.”

“Your father, Mr Dragos is the tenant named on the agreement isn’t he?” Jackie asked. “Is he in?”

“My father is unwell. He cannot be disturbed.”

“Unwell?” Maureen sounded alarmed. “Is he… I’m sorry but you must have heard about the deaths in the neighbourhood. Is… are you sure your father is…”

“I was attending to him a few minutes ago,” Claudia answered. “I shall have to see to his medication very soon, also. So I am sorry I cannot offer any further hospitality.”

Neither Jackie nor Maureen thought they had been offered any hospitality at all so far so they let that pass. Jackie looked around the living room. The furniture was the same furniture she had left when she leased it as a furnished property. But all the things that had made it her home were gone. There were no books on the shelves, ornaments, vases of flowers, fruit bowls, pictures on the walls. No mirrors either. The walls were blank and the cupboards and shelves and tables were bare.

A funny way to live, Jackie though.

There was something else, too. She touched the front of her dress over her extended stomach in an automatic gesture. She was pregnant with a Time Lord child and that had some unusual side effects that weren’t covered in any ordinary book on pregnancy. In particular it gave her a very low level telepathic sense. And she was feeling something right now that disturbed her.

Her baby didn’t like being in this room with these people.

“Well,” she said with false brightness. “I can see that you’re keeping the place neat and tidy. And the rent is paid on time. So there’s no need to bother your father right now. We’ll see ourselves out.”

She tried not to look like she was running, and in truth running was not an option for her anyway. If she tried she was liable to fall over and roll. But she moved as fast as she could. Maureen flanked her as they reached the lift and the doors opened almost straight away. She didn’t say anything though, until they were safe in Maureen’s flat.

“Those people!” Jackie said in a voice as steady as she could make it. “They’re aliens.”

Christopher and Mark slipped into the walk in cupboard as a shout went up in the corridor. Christopher opened the TARDIS door and ran to dematerialise quickly using the fast return switch that brought them straight back to their last location. If anyone checked the cupboard they would find nothing but an inventory that was missing two lab coats.

He turned from that manoeuvre to look at the results of the blood analysis. He was slightly disappointed to see that the TARDIS database had not identified the species that had bled that strange blood.

Then again…

“Father,” he whispered with a broad smile. “I’ve found a species that you don’t know about.” He felt rather proud of himself until he looked up and saw Mark watching him. Then he remembered that this unidentified species had killed nearly thirty people and felt more than a little ashamed that he had forgotten the reason he was on this quest.

He had been enjoying himself. He had felt the thrill of the chase, the adrenaline pumping in his veins. He had felt it like a natural high that his brain fed upon. He had understood for a while just what it was that drove his father to do things like this.

But he had forgotten the Human cost of it all, and he was sure his father never did that.

“Let’s get back to your mother and Jackie,” he said.

Jackie gave a cry of relief when she heard the front door of the flat open and Mark and Christopher both calling out at once. She would have jumped up from the chair if jumping was something she was capable of doing any more. She struggled up just in time to be hugged by her husband as he came into the living room.

“Hey,” he said to her. “No need to be so worried. I wasn’t in any danger.”

“I know but. The aliens. We know where they are. They’re living in my old flat. The aliens who did the killings.”

“What?” Christopher looked at her and then gently sat her back down in the chair and knelt by her side as she and Maureen told him everything they had discovered.

“Yes,” he said at last. “I think you’re right. They DO sound as if they MAY be non-Human. But is there anything that links them to the killings?”

“They’re aliens. Isn’t it obvious?”

“Not necessarily. They’re a family group, living in a flat, unobtrusively. They sound a bit foreign and they were nervous about you being there. They might just be afraid of being found out.”

“Well, yes. They’re aliens.” Jackie insisted.

“So am I,” Christopher reminded her. “And you don’t mind me?”

“No. But…”

“There ARE lots of aliens living on Earth,” he said. “There always have been. I know at least three government ministers whose ancestry on at least one side of their family is beyond this solar system. Humanoids have been coming to this planet for centuries looking for a peaceful existence. Your tenants may just be new arrivals trying to find their feet here.”

“I’m not sure,” Jackie told him. “When I was in the flat, I felt something. I’m sure I did. Something… something malevolent.”

“You felt something different and you were afraid because it’s different. You were afraid of my father when you first knew him, weren’t you?”

“Yes,” she admitted. “I was wrong then. But this time, I’m not. Christopher… you must believe me.”

Christopher looked at his wife. Jackie could be daft sometimes. But she wasn’t given to imagining things. Cruel people would say that was because she had no imagination. That wasn’t true. Nor were a lot of the things the same people said about her intelligence. He knew that better than anyone. He also knew that her advanced pregnancy gave her that latent telepathy and if she had a feeling something was wrong he couldn’t dismiss it entirely.

“I’ll check them out,” he promised. “But discreetly. If they are just newcomers looking for a quiet time I don’t want to alarm them.”

“Ok,” Jackie conceded. “So… what did you find out?”

“I didn’t find anything much,” Christopher admitted. “But the TARDIS did. All the victims were drained of cerebrospinal fluid. It’s the fluid that fills the spaces of the brain, basically. It’s… I suppose its engine oil for the brain. Without it the brain dies. That’s…” He took a deep breath. “I’m sorry. All those people. They must have hurt terribly for the time it took them to die. The old man we saw. He… he lived long enough to pull a gun on one of them. He shot it. But it escaped. It was bleeding, but it escaped.”

He showed Jackie and Maureen the photo of the handprint.

“Your tenants don’t have hands like that?” he asked.

“No, but that proves nothing. I was once attacked by a big fat policeman who turned out to have an eight foot green slime monster with massive claws inside his skin. RIGHT there in that flat where they live now.”

Christopher conceded that point to her.

“What I don’t understand,” Mark said. “How did the thing escape? It took you ten minutes to open the door with the sonic screwdriver. The door was locked like a fortress from the inside.”

“I had almost forgotten that,” Christopher admitted. And he mentally chided himself with the injunction that his father WOULDN’T have forgotten.

“Your dad gets things wrong, too,” Jackie told him. “Stop thinking you’re not as good as him.” She saw him look at her with a puzzled glance. “No, I can’t read what you’re thinking. The telepathy thing isn’t as strong as that. But I KNOW what you’re like. You always think you’re inferior to him, but you’re NOT. HE forgets things, too. And he’s still brilliant. And so are you. So… think. HOW could the thing have got out.”

“Wait a minute,” Maureen said. “Did the house you were in… Did the man have a cat?”

“Lots of them,” Christopher said. “The RSPCA man had a job collecting them.”

“That’s it!” Mark exclaimed. He looked at his mother and without needing ANY telepathy he knew that they had both thought of the same answer.

“What is?”

“Everyone who died had a cat. I saw the RSPCA van. There were half a dozen cats already in the back, belonging to people who died. And Miss Penny owned three white Persian cats. And Mr Lyndsay USE to have one but it was run over a while back.”

“Cats killed them?” Jackie looked puzzled. She hadn’t quite worked it out yet and was a little annoyed that everyone else had.

“No,” Mark said. “ALIENS killed them, then got out through the CATFLAP. Every one of the people killed had a catflap for their cats to get in and out.”

Maureen looked at the handprint picture.

“But this is too big to go through the catflap?”

This time Jackie HAD caught up.

“If eight foot slime monsters can fit into a Human skin I’m sure this thing can figure out a way to get through a catflap,” she said. Then she thought of something else. “Wait a minute. MY flat has a catflap.”

As she said that something banged on the front door and the letterbox rattled. Maureen’s flat DIDN’T have a catflap. She had never had a cat. But the thought of creatures coming in through a locked door made them all nervous.

Christopher stood up and warily stepped towards the hallway, pulling his sonic screwdriver from his inside pocket.

“Stay back,” he said as Mark, followed by Maureen, and last of all by Jackie who had to lever herself up from the chair, came behind him.

“What the HELL is THAT!” Maureen squealed shrilly. Nobody could blame her for doing so. THAT was a hand with only three long fingers and a thumb, on the end of a mottled grey-yellow arm that was stretched thin as it pushed through the letter box. The hand was grasping for the door catch, but even though the arm was strangely elastic it had limitations. It couldn’t get in far enough. And as Christopher ran for the door it retracted quickly.

He threw the door open just quick enough to see a mottled grey-yellow humanoid shaped creature with long thin arms and legs, a thin body and thin face morph into a regular shaped woman with black hair, pale face and blood red lips. She gave a shriek that was half Human voice and half animal snarl and turned to run. Christopher ran after her. She kept morphing from ‘Human’ to ‘alien’ form as if trying to decide which was best suited to flight. Both ways she was faster than a Human as she raced up the stairs. But Christopher was faster than a Human, too. He kept pace with her as she ran along the walkway towards Jackie’s old flat. She slammed the fire door in his face, but he pushed it open without breaking his stride and got there just in time to see her prove Jackie right. This alien species COULD get through a catflap. It did so by elongating its body and crawling like a snake, pencil thin arms by its side. He grabbed at an elongated leg, but the creature pulled and it slid though his fingers like a greased piece of rubber tubing. It was a feeling that made his skin crawl but he had no time to dwell on that.

“What IS it?” Cried Jackie and Maureen together as they, along with Mark, arrived by lift behind him. “Christopher..”

“I mean it this time,” he said. “STAY BACK. Whatever they are, they’re dangerous.” He adjusted his sonic screwdriver to lock picking mode and pushed the door open.

The dark haired woman was behind the door. Behind her were two others who looked identical to her in every respect except that one had a wound on her upper arm that he guessed might be a bullet hole.

“Clones,” he said. “That’s what you are, aren’t you? Clone servants who do the bidding of the old man?”

“Clever!” hissed the one he had chased. “You were right, sisters. This one and his friends have knowledge. Knowledge that is dangerous to us. Kill them.”

“We can’t use their fluid,” one of the sisters replied. “They are too young.”

“Not SO young,” said the first maliciously as she looked at Maureen and Jackie hovering behind Christopher, by no means as far back he meant when he said ‘stay back’. “But their necks will crush even if their fluids go to waste.”

Faster than he could have anticipated, the three women stretched once again into the snake like, elongated form. But they did not crawl this time. They launched themselves into the air, past Christopher as he tried to block the door. Jackie, Mark and Maureen all screamed as the foul bodies wrapped around their necks and began to squeeze.

“NO!” Christopher yelled. His fingers pressed quickly on the button that changed the sonic screwdriver’s function and dived towards Jackie. He grabbed the neck of the creature that was trying to strangle her and cut it off with the laser welding tool. The head screamed in agony as it and the lifeless body fell to the floor. Jackie gasped for air and watched as Christopher turned and cut through the torso of the one that had Mark in its grasp, then Maureen. She fainted in his arms as the creature fell from her neck, and Mark gave an anguished cry.

“She’s all right,” Christopher assured him as he laid her down on the concrete floor of the walkway, putting his jacket under her head. “You two look after her. I’ve got to go in there. There’s another one of them. The one that controlled these. But PLEASE, don’t follow me. You can’t do anything to help. And I won’t risk your lives.”

“I was right,” Jackie said. “I told you they were aliens. And I was right.”

“Yes,” Christopher admitted. “Yes, you WERE right. Forgive me for doubting you. And please, wait here until I get back. I don’t want you or the baby, or anyone ELSE at risk.

People were coming out of flats on the same level and crowding around. The word went about that Maureen had been attacked by a snake. The remains that lay on the ground looked snakelike at a first glance, though Christopher noticed one of the three fingered hands. It had a sort of rounded sucker in the middle of the palm that would clamp onto flesh and an auger like spike in the centre of it that would punch a hole.

That was how they killed, of course, and how they extracted the cerebrospinal fluid.

It explained HOW they did it. But WHY he intended to find out before he finished off the other creature.

It was in the bedroom, of course. He went straight to that room, recalling that Jackie used to sleep in there while he, when he stayed overnight, slept in the spare room that used to be Rose’s bedroom.

What was lying on the bed now made him forget such cosy memories. Once it must have resembled the basically humanoid shape of the three he had already killed. There were vestiges of a shrivelled torso and arms and legs like cooked spaghetti, as if the skeleton it no longer used had somehow been absorbed by the creature to sustain that part of itself that was in greater need – the head.

Even then, ‘head’ was too fine a definition. What it was, essentially, was a brain. A huge brain, a good three, four feet in diameter, lying on the bare mattress of the double bed. There was no skull, only skin stretched so thin that it was translucent. A face, or the impression of a face could be just seen. The eyes must have popped out of the empty sockets, and the nose and mouth were mere smudges. Christopher stared in horrified fascination as the brain pulsed with life.

Stolen life. He understood as soon as he saw it what the deaths had been for. This creature was sustained by the cerebrospinal fluid. The old people had been ‘milked’ to keep this monstrosity alive.

He felt sick at the thought. And he prepared to kill it. He drew his sonic screwdriver again, still in laser welding mode, and stepped forward.

He staggered back from the invisible field that sent pain raging through his body. The creature was defended. He couldn’t reach it physically.

Telepathically was another matter. He could FEEL that the huge brain was psychic. It had to be to command the three servants, since it had no working mouth to speak with. Now he felt it reaching out to his mind, searching to find out what he was.

“A creature of great age and wisdom!” He heard the words in his head, echoing strangely. “What are you?” He immediately blocked his thoughts before they could be read. But the creature had an answer in the millisecond that his mind was open. “Agggh… A Time Lord!”

“Yes,” Christopher answered it. “A Time Lord.” He thought the creature sounded just a little frightened of him. It knew he was a force to be reckoned with.

“What do you want with me, Time Lord? Where are my daughters?”

“They’re dead,” Christopher answered. “I killed them. And I mean to kill YOU. But first… What are YOU? And why are you here on this planet? Why have you murdered people?”

The answers didn’t come in words. Rather he saw them in pictures that crowded in on each other in a few seconds. Creatures such as this one travelled the universe, seeking out life that they could feed upon. He saw their name, Cephaloids, and he saw the planet they came from and fixed its position in his head.

“Why old people?” he demanded. And once again there was an answer. Somehow the creature seemed compelled to answer him. It struggled not to, but his mind was too strong and it had to give up its secrets. He saw that the cerebrospinal fluid of the very old contained a substance that sustained the Cephaloid and allowed its brain to grow as it did. When it reached the maximum size its mental powers were such that any planet it settled upon was at its mercy and the population could be culled at will, made slaves, used as food. Christopher didn’t recognise the chemical compound that it said it needed, but he mentally filed it away. Along with everything else he had learnt it would go into the Time Lord database of species in the TARDIS computer bank.

“You feed upon the weak and vulnerable old,” he said. “I am older than any Human being on this planet. FAR older. But I am neither weak nor vulnerable. Feed on me if you dare. But prepare to fight me first. I challenge you, creature. Feed on me if you can.”

He knew the creature would not refuse the challenge. He wasn’t sure if his brain fluids were any use to it. He wasn’t old by the reckoning of his species. But he had no intention of letting it find out. He had learnt to duel with his mind centuries ago. From an early age he and his father had played multi-dimensional chess using boards conjured by the power of the mind. Later he had met him in other mental challenges. He had honed his mind, sharpened it. True he had let his mental skills lapse when he was older, when he spent so much of his time in the chambers of the High Council where telepathy was discouraged and sometimes actively prevented. But the skills once learnt were never lost and his mind was ready to match the creature. It was sharp, and that was not just a metaphor. He used his mind like a dagger to stab at the creature. At first it rebuffed him and his whole body felt the pain as it returned blow for blow. But then he found a way in, a weakness, and he stabbed hard. He heard the creature scream mentally, and he felt it retreat from his mind. He was beating it. He felt a change in the pressure of the air around him and he stepped forward. The force field was gone as the creature’s mental ability was reduced. He slashed with his sonic screwdriver and saw a real, physical wound slice into the brain. Fluid, blood and brain matter poured out. He saw and felt its death as it sagged like a bag of… words failed him to describe what it looked like now it was dead. It was even more repulsive than before. But no longer any harm to anyone.

He turned and went back outside the house. Jackie, Maureen and Mark were waiting alone. They had persuaded the neighbours that the drama was over and there was nothing to worry about. He noted that the pieces of the dead creatures were gone.

“They sort of melted away, just now,” Jackie told him.

“When I killed the core creature,” Christopher said. “I think their bodies were maintained by its mental power. Without it they were nothing.”

“It’s dead then?” Maureen asked him

“What was it like?” Mark went as if to enter the flat. Christopher stopped him and pulled the door shut.

“You don’t have to see,” he said. “Believe me, you don’t want to see. I’m not sure what to do about the remains. But you do NOT want to see it. Come on. Back to your mum’s flat. I for one would REALLY like a cup of tea right now.”

Mark was disappointed. Maureen and Jackie were perfectly happy not to have to see the creature Christopher so emphatically told them they didn’t want to see. Maureen made tea and she and Jackie watched a daytime soap opera together that Jackie hadn’t seen for years. Mark came with him one more time down to the TARDIS. He was happy to sit there and watch as Christopher put everything he had learnt about the Cephaloids into a long, detailed report and filed it in the database. He also emailed it to his father’s laptop computer. He wasn’t at all surprised when, a few minutes later, the trimphone on the console rang.

“Yes,” was the answer to the unasked question that he knew his father would read between the lines of his report. “Yes, you did right. Killing that creature was the only thing you could do. Just like when I had to blow up Downing Street to defeat the Slitheen. Sometimes you come up against something you have to kill, for the sake of every innocent being in the universe. You did right. You did well. So don’t worry.”

“How did you know I was worried?” Christopher asked.

“Because I know you. I know I raised you to be a man of peace. But I also taught you that pacifism has to be fought for sometimes. Today was your first kill. And I know what that feels like. I know it’s not easy. But don’t waste any moment in regret. You did the RIGHT thing. By the way, when it died, was it messy?”

“Very,” Christopher answered. “Jackie’s old bedroom is a nightmare.”

“Call Torchwood,” The Doctor said with a laughing note in his voice. “They love analysing alien remains. They’ll clean things up nicely for you. If they do a good enough job, it might be worth rewarding them with the results of your analysis. Then they’ll know what to do if another one of those things wants to use Earth as a larder. By the way, congratulations on adding a new species to the database. That doesn’t happen TOO often these days.”

“People died. Innocent people. I take no pride in any part of this.”

“You used what you found to ensure nobody else died. You did well. You have EVERY reason to be proud. And I’m proud of you for remembering that Human cost. Now, go on and spend some time being Human yourself. Go back to Jackie and snuggle up and watch Coronation Street with her and I’ll see you when you get home.”

He put down the phone and looked around. Mark grinned at him.

“You don’t really want to watch Coronation Street, do you?” he asked. “Why don’t you leave mum and Jackie to do that and we’ll go down the pub for a drink?”

“Sounds good to me,” Christopher replied. “How would you like to take the scenic route. A slingshot around the moon and down to the pub car park? You deserve a proper ride in the TARDIS.”