“This is very pretty,” Romana said as she stepped out of the TARDIS into a small tropical paradise. Beneath her feet was a carpet of green grass and exotic flowers. One high cliff in the place the TARDIS had brought them to was hidden behind a curtain of overhanging vines while rock walls completed a circle with blue sky overhead. “Strange, though. A tropical garden enclosed by cliffs.”

“It’s the Umpherston Sinkhole,” The Doctor explained. In the town of Mount Gambier in South Australia.”

“Earth?” Romana was impressed. This planet The Doctor was so fond of really did have some impressive variations in its topography.

“Yes, indeed,” The Doctor replied. “The sinkhole was caused by the collapse of an underground chamber when rainwater leaching through the limestone roof weakened it. The sheltered place was left with fertile topsoil where plants grew naturally before a chap called Umpherston cultivated it and made it into a public garden. It remains a treasure of the city ever since.”

“I’m surprised. Humans never struck me as quite so creative.”

“Really?” The Doctor raised his eyebrows. “Remind me to take you to the Louvre to see the great works of one of the most creative humans ever to have lived. But right now, I’m interested in having a look around Mount Gambier. There is some unusual seismology in this area. The TARDIS detected it from space. It’s time for a nosy.”

“A nosy?” Romana took two steps to his one great stride holding down the straw hat that went with her almost school-girlish skirt, blouse and blazer ensemble. The Doctor was heading towards a beautifully finished wooden walkway and steps that led out of the sinkhole. In deference to the warm South Australian summer he had left off his long coat and was in shirt and waistcoat, but he still had his utterly ridiculous woollen scarf wound twice loosely around his neck and still dragging on the ground.

They emerged into a pleasantly laid out public garden where people could sit and relax on benches, but The Doctor wasn’t interested in relaxing. He strode on up to the four lane carriageway that took traffic past that haven of peace where they had landed. Romana was surprised to find that they were on the outskirts of a sizeable city with all that implied in terms of people, buildings, noise and bustle.

“This will do nicely,” The Doctor said, stopping by a bus stop. Romana vaguely knew what a bus was from visits to London and other cities on Earth, but she had never travelled on one before. She wasn’t sure this was going to be an especially edifying experience.

The bus came. The Doctor let her step aboard first. She sat down and watched him fumble in his pockets for loose change to pay the fare. She wondered vaguely how he managed to have currency for this place and time among the detritus he managed to keep in those pockets. Perhaps he didn’t. He may have paid with Vetrusian half ducles and hypnotised the driver into accepting the coins as legal tender. It was a minor infringement of the rules of time and space travel, but The Doctor really only felt guilty about the large fractures, not mere infringements of such rules.

He came to sit next to her as the bus moved on. The route continued along the East Jubilee Highway past a long, low building housing the South Australia Forestry before turning down a narrower road into a residential area. The houses and community buildings, including a home for the elderly and a large school taking children from kindergarten to eleven years old, were all single storey buildings. Romana found that strange. To her a city was more like the Capitol on Gallifrey with its soaring spires. New York or Hong Kong best fitted her definition.

“This area is susceptible to extreme winds at certain times of year,” The Doctor explained telepathically, catching her thoughts. “Typhoons, tornadoes, hurricanes. Low rise is safer than high rise in that kind of weather. People just batten down the hatches and wait it out in their cellars.”

“To see if there is a house left above them when it is over?”

“Unfortunately, yes.”

“Why do they live in such a region if they risk losing everything they own?”

“Because humans are magnificently tenacious and illogical,” The Doctor answered. “The most illogical people in the twelve galaxies. But wonderful, with it. Remember Skaro – the logical Daleks and Movellans, unable to move on from their stalemate war. Illogical humans beat Dalek logic every time.”

“Yes, but don’t humans also have a reputation for the most unpleasant wars among themselves?”

“That’s because they’re still children in terms of intellectual development. And they don’t employ logic to their disputes. Quite illogical people, humans.”

So was The Doctor, Romana noted.

Then she suppressed a squeal of fright as the bus driver slammed on the brakes hard. All of the passengers slid forward in their seats, stopping themselves from falling further by reaching out to the back of the seat in front of them.

All except for The Doctor whose broad-shouldered frame was sticking out from the narrow seat. He fell forward all the way to the front of the bus, coming to a halt on his knees in front of the wide windscreen.

Which meant that he had the best view of what made the driver stop the bus.

A hole – the word sinkhole immediately popped into Romana’s mind as she observed the situation – had appeared in the road a few metres ahead. A car just in front of the bus had driven right into it, unable to stop in time.

The Doctor was on his feet in an instant, pressing the emergency door handle and leaping out of the bus. Romana followed but by the time she got there The Doctor was already using his scarf as a rope to help the passenger in the car to climb back to what they had to hope was solid ground.

The passenger was the brother of the driver and he called out to him, but to no avail. The car was sliding sideways down the hole with the other man trapped inside. The Doctor made to climb down, but the bus driver and another man held him back.

“It’s no good, mate, he’s a gonner and you will be too if you try anything.”

Reluctantly The Doctor had to concede that they were right. He watched helplessly as the car slipped away and a fall of soil and gravel covered it over leaving a perfectly clean bottom to a sinkhole a quarter of the width and not even half the depth of the famous one just a bus ride away.

The rescued man was distraught. Romana spoke gently to him, and with a little applied Power of Suggestion persuaded him to come and sit in the bus until the emergency services arrived. The Doctor, meanwhile, was using his sonic screwdriver to examine the edges of the sinkhole.

“Amazing,” he murmured. “It’s almost a perfect circle. Do you know what the chances of that are, Romana? Perfect circles are rarely formed naturally.”

“I’ll take your word for it, Doctor. Just don’t even THINK about climbing down there. You don’t know how stable that floor is.”

“I doubt that floor is stable at all and I have no intention of going down there,” The Doctor assured her. “I’m afraid the driver would be dead, anyway. There’s precious little hope for him.”

He removed his hat when he said that and bowed his head. Romana quickly copied him. Then he turned and began running towards the playground of that single storey school that she had commented about. The children had been at play, but the drama on the road had brought their games to a standstill.

“Get the children inside,” The Doctor called out to the teachers on playground duty. “No, not that way. Take them in by the east door. Keep away from the west end of the school. There’s another sinkhole due, and it’s along this line.”

How much of that the teachers understood amidst the shouts and cries of children disturbed by the crazy-eyed man running towards them was moot. Even so, they reacted immediately, blowing whistles and organising a sort of reverse of the school fire drill, sending the children inside with as much calm as they could muster in the circumstances.

But he was right. Even as the last child ran into the school a sinkhole appeared in the middle of the playground. It did so suddenly, as if an invisible giant with circular feet had stamped down. The Doctor stood back at first, then ran to the edge of the hole and took his mysterious measurements with the sonic screwdriver.

“What is going ON, Doctor?” Romana asked. “Two holes in a few minutes – and you predicted where the second was going to appear. How?”

“Tremors,” he answered. “The sonic detected them. Micro-tremors beneath the ground. I didn’t know exactly where it would appear. There was a risk it could have been under this end of the school building. That’s why I sent them through the other door. But come on. We can’t stop here.”

He ran towards the west entrance to the school, to where the kindergarten and infant children usually went in after their break. Romana, following him, noticed stick figure paintings adorning the walls of the corridor that continued right through to the back of the school.

“Doctor!” Romana looked into one of the classrooms and noticed a boy of six or seven busily wiping the whiteboard – obviously a punishment for some infraction in his lessons. She opened the door and called to the boy. “Come on, it’s not safe in here. Quickly.”

The boy dropped the whiteboard eraser and ran towards her, and not a moment too soon. As she grasped his hand and pulled him across the threshold his classroom collapsed into another sinkhole. The class pet, a thoroughly enraged cockatoo, escaped from its cage and flew out after him before everything else was swallowed up.

“Keep moving,” The Doctor said. “This isn’t over.”

They reached the front of the building in time to see the school minibus fall into another hole while the caretaker, who was washing it, jumped to safety.

“Take this little boy to the east entrance where everyone else went,” Romana said to the distressed man. “The Doctor seems to think you’re all safe there.”

“You ARE,” The Doctor insisted. “These sinkholes are on an almost exact north-north-west line. That side of the school is safe.”

The caretaker took his word for it and ran with the boy towards the other door to the school. The Doctor, followed by Romana, headed out through the back gate in time to see first one and then the other set of goal posts in the wide playing field disappear into sinkholes.

They ran on, both using their Gallifreyan ability to recycle their breathing so that they didn’t get out of breath before they reached the next suburban street where a parked car was swallowed up.

“That house,” The Doctor said, charging across the road and in through the front gate of a sprawling red-roofed bungalow. He ran through the drawing room and kitchen and came out into the back garden just as the parents grabbed their children from the paddling pool and stood watching their garage tilt sideways before falling into the next sinkhole.

“Stay in your home, you’re safe now,” The Doctor called out to the terrified family before he vaulted over the fence that divided one tract house from its neighbour behind. This house had a swimming pool, or it did. The swimmer clambered to safety, helped by The Doctor and Romana just as the bottom dropped out of it and the water poured away.

“Lucky escape,” Romana told the swimmer, passing him a towel from the deckchair beside the ex-pool. The Doctor was already racing through the house and was in time to see the front wall of the house across the road fall into the sinkhole that appeared in the garden.

“Somebody else is going to die,” The Doctor said as he again took a direct route, through the houses and gardens until he emerged, closely followed by Romana, on what looked at first like another dual carriageway with a central reservation. It was only when a sinkhole appeared in the middle, that the two Time Lords noticed that there was a single track railway line there and a whole separate road on the other side.

“I think it’s disused,” Romana noted with relief, examining the rusty rails and crumbling sleepers. “Thank goodness for that.”

Then she cried out in shock as a loud crash followed by an explosion signalled that a sinkhole had undermined part of the large factory on the other side of the road. At the same time the sirens of emergency vehicles arriving at the scene of multiple devastations filled the air.

“Doctor!” A voice called out over the noise. The Doctor and Romana both looked around. It sounded like an urgent greeting rather than a plea for medical attention. They both saw a blue and white van with a satellite receiver mounted on top. A man waved from the passenger side. The Doctor hesitated briefly before running towards the van.

“It is you, isn’t it?” said the driver who was wearing a t.shirt with a picture of a grey, slant-eyed alien on the front. “I’ve seen pictures of you on the conspiracy sites. I never expected to see you in the flesh, but now is the best possible time. Hop in, mate. We need you.”

A side door slid open. The Doctor and Romana jumped into the van which immediately reversed and took a north-north-easterly road back into the midst of suburbia. The driver was following directions from a young man in a t-shirt bearing the words ‘I am the people my parents warned me about’ who was sitting on the floor in the back of the van looking intently at a laptop screen. While Romana sat comfortably in the front seat, The Doctor stretched his long legs out beside the young man and took notice of the data scrolling down one side of his screen next to a GPS map of their route through the suburbs of Mount Gambier.

“You’re predicting where the next sinkhole will appear,” The Doctor said in a suitably impressed tone. “Very clever. You are….”

“Eric Snod, PhD – director of the Mount Gambier Institute for Extra-Terrestrial Research.”

“M-GEITeR for short,” the driver added. “I’m Nick Swann, junior researcher.”

“And how many other people work in your Institute?” Romana asked in a slightly suspicious tone.

“My sister compiles data for us,” Nick admitted. “She’s a statistics geek.”

“And….” Romana’s suspicions were well-founded. “Where is your Institute? Is it attached to a university?”

“Not exactly ATTACHED,” Eric was forced to concede. “More… not attached. It’s mostly the basement and two rooms of my house. But… the house IS mine. I don’t live with my parents or anything sad like that. I made my house into the centre for my research.”

The Doctor didn’t make any comment, but the expression on his face spoke volumes.

Eric smiled wryly.

“I know what you’re thinking. The PhD is real, honestly. I was a child genius. I got it when I was fourteen. When your name is Eric Snod you don’t get many distractions, after all. But… Doctor… it’s amazing to meet you. I’ve seen ALL of your faces on the net. I hoped I’d bump into one of them in the course of my investigations, and here you are, right here in my home town, and we’ve got an alien mystery to solve.”

“Yes, we do,” The Doctor agreed when Eric gave him room to get a word in.

“Are you really alien yourself?” Nick asked.

“Yes, we both are,” Romana told him. “Please try to stay calm about it.”

“Calm? There’s a gorgeous alien woman sitting in the passenger seat of my van and she wants me to be calm? It’s a wonder I’m not doing handstands.”

Romana smiled sweetly at the ‘gorgeous’ bit and advised him not to attempt to drive while doing handstands.

“I notice that we seem to be leaving the city now and following this long, straight road between fields.”

“Kennedy Avenue, yes,” Nick confirmed. “It goes on for miles like this. That’s a bit of a relief, anyway. Less chance of innocent people getting hurt.”

“Your predictions are not quite accurate,” The Doctor told Eric. “The sinkholes are getting further apart.”

“You’re quite right,” Eric agreed. “It’s running out of steam. I mean… not steam, obviously. But the phenomena DOES seem to be running out of energy. It did that yesterday, too. After about an hour it slowed right down and made less and less frequent sinkholes before it finally stopped.”

“It’s detecting less vibrations now that it’s outside of the city,” The Doctor said. “That’s why there were more holes in the most densely built up part of town it hit – especially around the school. All those little feet running up and down the playground. Thank goodness there wasn’t a football match on the playing field. How far have you followed the micro-tremors?”

“From Blue Lake about an hour ago. Yesterday, they ran in the opposite direction, under the mountain and into the countryside. There were less casualties. This morning we were monitoring the lake when we picked up the tremors again and followed them.”

“I’d like to see what it all looks like from the air,” The Doctor said. “I don’t imagine you two have access to a helicopter?”

“‘Fraid not,” Nick admitted. “This is our only mobile unit.”

The Doctor smiled at the description of the bare van and the laptop balanced on a plastic picnic cooler as a ‘mobile unit’ and made a decision.

“It’s your big day, my friends. Nick, turn around and head to Umpherston sinkhole.”

“Is that something to do with what happened?” he asked as he did a very neat u-turn on the empty road. “Was the Umpherston sinkhole caused by the same thing?”

“Not that I know,” The Doctor answered. “It is where my space ship is parked.”

Nick pressed his foot down on the accelerator. Romana yelped with the sudden increase in speed

“The TARDIS isn’t going anywhere without us,” she said. “You can stick to the speed limit.”

Nick slowed down a little and chose the most direct route to the tourist attraction, shaving several minutes off the journey due to his familiarity with the neighbourhood. He and Eric, clutching his laptop, hurried after The Doctor and Romana. When they saw the TARDIS parked in the grotto they all but hugged each other.

“It’s REAL!” they exclaimed in unison.

“Come on, then,” The Doctor said as he opened the door. “Don’t worry about the ‘bigger on the inside bit’. We’re too busy for all that.”

Romana followed The Doctor over the threshold and then looked back at the two young scientists.

“Come ON!” she urged them. They sprang forward and made it inside just before The Doctor reached for the door control.

“Wow!” Again they were in unison.

“Eric, your laptop, please,” The Doctor said, keeping to the point. Eric handed it over and was shocked when The Doctor opened it up and pulled the hard drive out of it. He interfaced it directly with the TARDIS console and downloaded all the information that had been gathered over the past days.

“Don’t worry,” Romana assured Eric. “I can fix that in a few moments.” As The Doctor set their destination and dematerialised the TARDIS, Romana used an ordinary non-sonic screwdriver to put the laptop back together. It took only two minutes for her to complete that process and for The Doctor to materialise the TARDIS in mid-air above the Blue Lake.

It was quite obvious even to the naked eye that there was something not quite right about the lake. It got its name from the perfectly even cobalt blue colour of the usually tranquil water, but just now the colour was far from even and the water anything but tranquil. There was a swirling whirlpool of turquoise in the middle with white foam around the edges and concentric ripples radiating out from that point, changing the colour all the time.

Something was obviously happening under the water.

“Why hasn’t anyone realised this was happening?” Romana asked. “Surely it must be obvious even from ground level, and it’s not as if this is a remote lake. It’s close to the city. People must go here all the time.”

Even as she spoke, though, the whirlpool stilled. The concentric ripples died away and the deep cobalt uniformity returned to the surface of the lake.

But what lay beneath it, causing the disturbance they had witnessed and how did it tie in with the sinkholes that had caused such devastation across the suburbs of Mount Gambier?

The Doctor fully intended to find out. Even Romana was a little startled when the TARDIS began to descend rapidly towards the lake, though. Even though she knew that TARDISes were fully submersible she was a tiny bit anxious as they dropped beneath the surface. The viewscreen darkened gradually as they got deeper, and then lightened all at once as the TARDIS passed through a kind of membrane that was holding back the water from a peculiar chamber.

“What is THAT?” Romana’s voice joined in unison with the voices of the two Human passengers as they looked at the peculiarly amorphous mass outside. It might have been a huge brain, or a lung, or a liver. It was organic in some way, that much they could all agree.

“It’s what I was starting to suspect,” The Doctor answered. “There’s an oxygen atmosphere out there. All ashore who’s going ashore.”

That was his way of saying that the humans could come along outside with him, though at their own risk. They all stepped out of the TARDIS and looked around the chamber. It was a rough hemisphere, the membrane holding back the lake looking far too thin for the purpose. Silvery veins ran through it, and through the blue-pink surface they were standing on, which looked too much like flesh for comfort.

“Tell me this isn’t the STOMACH of some monstrous creature,” Romana pleaded. Nick and Eric were dumbstruck by such intimate contact with a non-humanoid alien and had nothing to say.

Well, almost nothing.

“Doctor… there are people over here,” Eric called out. The Doctor was there in a few quick strides, his sonic screwdriver ready to analyse the blue-pink veined organic pods that the humans were contained within.

“Some kind of life support system,” he confirmed. “They’re alive.”

“This one is the man whose car was swallowed up by the first sinkhole we saw,” Romana said, closely examining one pod. “I don’t know about the others.”

“Those look like they were exploring the caves on the other side of Mount Gambier, yesterday,” Eric observed. “And that poor beggar is a countryside ranger. He’ll have been reported missing yesterday, too, I’d say.”

“There’s a blooming kangaroo in this one,” Nick called out. “Poor old thing.”

“They’re not dead,” Romana pointed out. “That’s the important point. Doctor, we can rescue them?”

“No, but we might be able to reason with their captor. I don’t think it meant to harm them, hence the life support. I don’t think it knows what to do with them, though.”

He turned to the amorphous organic mass, a darker pinkish-blue than its surroundings. It pulsated in a manner that was repulsive to the senses of humans and Time Lord alike – Or a Time Lady, at least. The Doctor didn’t have any qualms about stepping close enough to touch it.

He didn’t ACTUALLY touch it. He raised his hands and closed his eyes. Romana felt his telepathic connection with the mind within that mass. She knew it had one, now. She hadn’t recognised it at first, a fact which chastened her a little. She salved her conscience by reminding herself that her first concern had been for the captives.

Yes, there was a mind. And it was the mind with an insatiable curiosity – much like The Doctor, she realised as she felt the two communicating with each other. It had come to Earth for the same reason he had – to experience new things.

“Oh, goodness me,” she gasped aloud as she understood. The language that the creature was communicating in wasn’t one made up of words, but physical sensations. Even so she felt it explaining about its home world where it lived in a body of water not unlike the Blue Lake. Other creatures like it lived in similar lakes, and they communicated with each other by sending out small offshoots, tentacles, tendrils – there really wasn’t a word in any spoken language for them – that connected with their neighbours in the other lakes.

“That’s what it was doing… reaching out for others?”

“Other what?” Eric asked. Romana explained quickly.

“But there isn’t another lake for hundreds of miles,” Nick responded. “And even if there was… there wouldn’t be another one of these in it.”

“Yes, that’s the trouble. It was getting desperate. That’s why it had been so rough about it, causing sinkholes all over the place. It rescued the air-breathing creatures it accidentally disturbed… it didn’t mean that to happen… but when it felt their vibrations it mistook them for the movement of its fellows in their own lakes. And all that effort exhausted it. Eventually it had to give up and rest before trying again.”

“It’ll keep on trying,” Eric pointed out. “If it tries to reach out under the city centre next time, not the suburbs, it could cause all kinds of devastation.”

“Yes, The Doctor is explaining that. And he’s explaining that the creature and its fellows made a terrible mistake. On a planet with so many oceans they landed on one of its hottest, driest landmasses. This one was lucky, but its companions would have died in the heat of the Australian outback. Their exploration here was a disaster.”

“Oh!” Eric and Nick both stepped closer to the creature’s brain sac. They reached out, though without touching. “Hey, mate, we’re sorry about that. Australia is a bonza place for us land-living sorts. But not such a good place for you to visit.”

“It feels your sympathy,” Romana told them.

“Is there anything we can do?” Nick asked.

“Nothing any Human can do,” The Doctor replied. “But I’ve promised to help get it home. First the casualties. We’re going to bring them into the TARDIS.”

The life support pods were dissolving from around the accidental victims of the creature’s attempt to reach out, but the people and the luckless kangaroo were still in a kind of stasis. They needed to be carried and laid on the TARDIS floor safely.

“All right,” The Doctor said when that was done. “Now everyone inside. The membrane is going to collapse soon. The creature is going into travel hibernation state.”

That didn’t sound like something anyone wanted to wait around for. Nick and Eric got right back into the TARDIS. Romana was with The Doctor at the console. She understood what he planned. The creature had to complete its hibernation, first, though.

“Does it have any kind of designation?” she asked as they watched the membrane dissolve and the creature fold itself up into a tight ball with a strong, yet organic outer casing rather like an aquatic armadillo. “I mean… we’ve all called it the creature… does it have a species, and do the individuals have names?”

Nick and Eric nodded in agreement. That was something they felt they wanted to know, too – in the interests of extra-terrestrial research.

“It’s a No’oma,” The Doctor answered. “From a planet called No’om. It’s individual name is O’ae.”

The information was of no real use to anyone, but it was strangely comforting to know, and Romana was right. Calling it O’ae was better than calling it ‘the creature’.

O’ae was ready. The Doctor moved the TARDIS closer to it and carefully extended the external gravity towards it. Then he re-calibrated the dematerialisation so that O’ae, clinging like a limpet to the outside of the TARDIS, was safely brought through the vortex with them.

“Hey, wait!” Eric exclaimed as he looked at the image of the swirling vortex on the screen. “Do you mean that we’re going to another planet?”

It was almost worth being born Eric Snod to experience something few other humans had ever experienced – leaving the gravitational pull of planet Earth. In his century that elite group only included a handful of astronauts, a few people who had met The Doctor from time to time, and some unfortunates kidnapped by more sinister visitors who filled conspiracy forums on the internet with their abduction stories and theories.

Eric appreciated the honour thoroughly, especially when the TARDIS came out of the vortex into orbit above No’om. A planet made up of cobalt blue lakes separated by a fragile-looking fretwork of dry land was beyond the imagination of any conspiracy theorist.

The Doctor brought the TARDIS into the upper atmosphere before letting O’ae freefall down to his own world. They saw the travel casing break open either side to allow two translucent wings to spread wide. They didn’t flap like a bird’s wings, but they let him make a directed glide down to an empty lake where he could settle down before reaching out to his neighbours.

“Not bad,” Nick commented. “Not bad at all.”

“We’d better get you two and these other people back, now,” Romana commented, looking around at the sleeping passengers who had missed all of that. Nick and Eric were a little disappointed, but after all, they had travelled in an alien ship to another world. What more could they ask for?

They asked The Doctor and Romana to stick around for a bit. While the South Australian division of U.N.I.T. took charge of the missing people and put out a cover story about collapsing limestone bubbles deep in the subsoil, they enjoyed the sunshine at Umpherston Park. Nick and Eric organised a barbecue and Nick’s sister who was good at statistics arrived along with some other friends who might be considered geeks and uncool turned up to enjoy their moment of vindication.

The Doctor and Romana enjoyed the party and fielded as many questions as they dared without breaking any Laws of Time or any secrets of Gallifrey before they waved goodbye and stepped into the TARDIS. The select group of Mount Gambier alien theorists had a moment of sheer delight as the police box dematerialised and the two Time Lords went on to their next adventure.