"Ah,"
"Ah?"
"Ah."
"Is that an 'ah, I've found something interesting,' or an 'ah, we're all going to die?'"
"Can't it be both?"
Amy gave the Doctor the look she'd been finding increasingly useful these past few months. It was an elevated left eyebrow look, one which clearly said, 'are you quite mad?' Of course, she'd long ago realised that the answer to that question was a definite yes, but that didn't stop her developing eyebrow-raising to a fine art.
Currently leaning over the central console, the eccentric time traveller was not exactly inspiring confidence in his work. Holding a handful of exposed wires in one hand and something that looked very much like a kazoo in the other, she couldn't remember ever seeing him look more like a mad professor.
"Look, can you fix it or not?" she demanded.
For perhaps the third time in as many days, the TARDIS was refusing to play ball. The Timelord's repeated attempts to get the engines running again were proving thoroughly unsuccessful, and Amy was beginning to lose her patience.
"It's not that simple," the Doctor explained. "The TARDIS isn't just something you fix, she's a living thing. You more have to... persuade her to start working again."
"How do you..." she began, before holding up a hand. "No, forget I asked."
Emerging from the corridor, Rory entered the room dressed in a pair of swimming shorts, scrubbing at his head with a towel. Drips of water were scattering off him, forming a small pool around his feet.
"Watch the wiring!" the Doctor hissed, as his companion approached the console. Stepping backwards from the Doctor's work, Rory took up a perch a safe distance from the other two, leaning against one of the railings that surrounded the centre of the control room.
"Still broken I take it?" he asked.
"Yep," Amy replied. "How was your swim?"
"It was going really well until the fish turned up."
Amy raised the other eyebrow. "The fish?" she asked.
"Yes," Rory nodded in reply. "There's a load of fish in the swimming pool."
Amy looked confused. "Then why did you get in?" she asked.
"Well they weren't there when I started. Then twenty lengths later, thwop, fish."
"I don't believe you," she replied.
"See for yourself."
"No. I don't believe you could manage twenty lengths without passing out."
Rory ran his fingers through his hair, then flicked a handful of cold water at Amy. Squealing in protest, she stepped away from her husband.
"What do you mean, thwop?" she asked a moment later.
"Thwop. That's the sound the fish made when they appeared."
"Aha!" exclaimed the Doctor, suddenly taking an interest. "What kind of fish?" he asked, clambering out from underneath the TARDIS console.
"I don't know, blue?" Rory replied. "Does it matter?"
"Possibly not, but a single Malengan trout provides the same power output as a type three fusion reactor. Just one of those could have provided the jump-start we needed right now."
"Want to check it out?" Rory asked.
"Not much point, a Malengan fish would have also turned you to atomic residue before absorbing you through its gills for food."
"Oh," muttered Rory. "Sorry I couldn't be of more help."
"The question is," the Doctor continued, barely listening, "why the swimming pool? Why the fish, and above all else, how and why did they thwop there?"
He turned to the console and began feverishly making calculations on the main computer.
"Think about it," he instructed. "Every planet in the universe orbits their star at a staggering speed. Now each of those stars orbits the centre of their galaxy. Those galaxies are hurtling through space at an unimaginable rate. The TARDIS is one of the most complicated devices in the universe, but even so I still sometimes struggle to hit the planet I'm aiming for. And you're telling me a shoal of fish just happened to thwop into the middle of a tiny blue box somewhere in the universe, and not only that, they just happened to land in a swimming pool? No, the fish, the pool, the kazoo... It all just seems a bit too improbable."
"A theory?" Amy asked.
"A theory!" the Doctor exclaimed, raising a finger in triumph. His two companions looked at each other for a moment with apprehension, but decided to listen anyway.
"Now then," he began, "there are moments in time that are fixed; unchangeable times where whatever happens, happens. Times that the universe and everything in it rely upon. Then there are the fluid moments where events can be changed. Slippery moments that act like the lubricant in the gears of the universe."
"We know Doctor, you've told us this before," Amy commented. "And more than once, I might add."
"But then there are the other moments," he continued. "The moments where time and space collide in chunks of wibbly wobbliness and bounce off in all different directions. These are the moments where events mean nothing, where cause follows effect before following cause again. Probable becomes improbable, unlikely becomes likely."
"But that doesn't make any sense," Rory pointed out.
"Of course it doesn't, that's the whole point. They're the fleeting moments when you catch a glimpse of someone in the corner of your eye who can't possibly be there. When you put down your keys for just a moment and then find them in another room two hours later."
"That's just life playing tricks on you," Amy argued. "It's not real."
"I thought that once, then I met a man named Schrodinger," the Doctor replied. "Poor fellow. A lovely man he was, shame about his cat."
"What cat?" Rory asked.
"Precisely."
After a brief pause made it clear that the Doctor had no intention of elaborating, Amy stepped back in to continue the conversation.
"So this is one of those moments?" she asked.
"Might be, it's very difficult to tell," the Doctor replied. "It would explain why the TARDIS can't figure out where we are, and why I can't get her moving again." He paused and scratched at his chin. "Do you know where your keys are?"
His fingers clattered across the surface of the TARDIS console and a screen blinked into life.
"Right then. According to this, we're stuck in a bubble of improbability. It's very difficult to be certain of anything right now, but all I know is that right now outside that door could be absolutely anything."
Rory raised a finger. "And that's different to normal, how exactly?"
"I mean anything," the Doctor replied. "It could be a world made of jelly, a jelly made of worlds. It could even be something completely non-jelly related."
"Are we in danger?" Rory asked.
"The TARDIS should protect us from the majority of its effects," the Doctor replied. "Even so, the odd thing will still manage to slip through."
"Like the fish?"
"Precisely. And the kazoo." He lifted the offending instrument to his lips and blew an unpleasant rasp.
"So why are we stuck? You say these things happen all the time." Rory asked.
"They do, the chances of one interfering with the time stream are infinitesimally improbable. The problem is, improbable things are quite likely round here."
"But how can you be sure?"
"An experiment!" the Doctor exclaimed.
Rory rolled his eyes. Despite his fondness for the Doctor, he was never particularly enamoured with the time-traveller's delight in experimentation. Things had a tendency to turn out...surprising. Clambering out from under the console, the Doctor finally emerged with a small cloth bag, then extended it to Amy.
"Close your eyes," he said. "I want you to reach inside this bag at random and pull out a billiard ball.
Amy shrugged and dipped her fingers into the bag. After a moments fishing around, her fingers retreated, a black eight-ball clutched triumphantly in her grip.
"Tadaa!" she exclaimed. "Why have you got a bag full of snooker balls, anyway?"
"Billiards, not snooker," the Doctor corrected. "And I don't," he added, turning the bag inside out. "The bag's empty."
"I don't understand," Amy responded, mirroring Rory's feelings precisely.
The Doctor buried his head back in the console, snapping levers backwards and forwards and jabbing at buttons ferociously.
"It means," he replied finally, "that our thoughts and expectations are having an impression on the probability matrix. It means anything you say, do or even think can have an impact on reality itself. Above all else, it means trouble."
"I thought you said we were safe?" Amy pointed out.
"The TARDIS shields should be protecting us, but probability seems to be breaking down at a local level, so I can't exactly be certain."
"So what can we do then?" Rory asked.
"There's a way out, there must be a way out. If there's one thing I've learned over the centuries there's always a way out. So sit quietly and let me find it."
He paused.
"Oh" he finally added, "and try not to think about anything. Especially not anything really, really dangerous."
He paused again.
"And Rory, go put some clothes on."
A short time later, a rather more presentable-looking Rory re-entered the console room, finding it looking much the same as when he'd left it; Amy slouching in a seat with a bored look on her face and the Doctor poking and prodding at the underside of the console. Occasionally, either the whirr of the sonic screwdriver or the Doctor's continual inaudible muttering would fill the silence, but otherwise it was surprisingly quiet.
Suddenly, a massive jolt shook the control room and hurled the occupants to the floor.
The Doctor stood up and straightened his tie. He looked disapprovingly at his companions. "One of you thought about something really dangerous, didn't you?"
Rory looked sheepish, Amy even more so. They looked at each other.
"It wasn't me," they responded in unison.
The Doctor rolled his eyes. "One job, just one thing I ask you to not do, and you do it. Or rather you don't not do it, when you shouldn't do it. So stop not doing it."
Amy and Rory looked at each other and shrugged.
He hammered a few buttons on the console. "Right, I've realigned the shielding for what good it'll do, but do try and think of fluffy kittens from now on."
For what felt like an eternity, the two of them stood there, both trying desperately not to think of anything more dangerous than a soft cushion.
"Aha!" the Doctor finally announced, raising his arms in jubilation. His companions sighed in relief.
"You fixed it?" Amy asked.
"No!, but I have an idea. Well, more an idea of an idea; an inkling of a suggestion even," the Doctor explained. " We need a lynchpin, a fixed point in the universe, an indisputable fact in time and space that we can grab onto and drag ourselves out of this hole. And I think I know just the man."
"A man?" Amy repeated.
"Yes. The problem is I don't know where he is, and with the TARDIS scanners not functioning outside of the bubble, I've got no way of finding him."
"No idea? Not even a guess?" Amy asked.
"Guess? I can't just guess. The TARDIS will be torn apart if I anchor us to the wrong point. Fixed spatial coordinates are a combination of over a dozen values that change constantly. The chances of me hitting the right value are..."
He paused.
"FISH!" He suddenly exclaimed, turning on Rory with an accusing finger. "You were thinking about fish!"
"I was not," Rory replied defensively.
"Not just then, in the pool, when you were swimming. You were thinking about fish, weren't you?"
"I'm not sure, I can't remember. No, wait. Yes, I was remembering diving in the sea on holiday. We ended up in the middle of a gigantic shoal."
"These fish, were they blue?" the Doctor demanded.
"I'm not sure...I...no, wait, they were. They were bright blue, just like the ones in the pool."
"The bubble is in flux, so thoughts can influence reality," the Doctor considered, almost to himself. "Both your thoughts and mine can influence this tiny little bubble of reality," he continued, turning slowly on the spot. "We alone decide what is real and what is not."
He stopped and raised an arm, pointing his finger into the distance. "And I say, he's that way."
After skipping across to the console, the time-traveller ferociously began tapping away at a brass keyboard, a look of concentration furrowing his brow.
"Are you sure?" said Amy.
The Doctor snapped back at her. "I have to be sure, that's the whole point. I think, therefore he is. If I'm right, we now exist in a reality where I can through sheer chance alone guess the exact temporal and spatial coordinates of a man I haven't seen in nearly fifty years."
He tapped in the last coordinate and placed his hand on the control lever.
"My people have an old saying," he said. "It doesn't matter whether you're right or wrong in life, as long as you're certain."
He paused, and for a moment, a look of doubt appeared to cross his face. Looking at his two companions, he said quietly "But If I'm wrong, we die."
Amy extended one hand and clasped Rory's outstretched palm. Extending the other towards the Doctor, she smiled.
"Geronimo" she commented.
Taking her hand, he grinned, then slammed the lever forwards.
ELSEWHERE
Running a bar on an isolated trading station was not the most exciting job at the best of times. Tonight was proving to be no exception. The usual galactic traders had retired for the evening, leaving the bar near empty, but despite this, a few hangers on still sat nursing their drinks and showed little intention of leaving. Isac stood behind the bar, idly passing the time between serving his customers by making a crude sketch of one of his patrons. His artistic skills weren't exactly top-notch, but at this time of night he didn't really have much else to do.
His subject for the evening sat a short distance from the bar, quietly drinking on his own like pretty much everyone else. What set this man out from the others was his rather unusual attire. Dressed in a blue shirt with a long grey coat slung across the chair next to him, he stood out from the pilots and workers who usually came to the bar still dressed in their overalls. His outfit was clearly old, marked with a number of stains and what looked like scorch marks, but it was worn with the confidence of a favourite outfit someone had no intention of giving up any time soon.
As the stranger spilled his glass, Isac rolled his eyes and reached for a cloth. His irritation rapidly turned to concern, however, after seeing the look of pain on the stranger's face. The patron was clutching at his chest and gasping, his face rapidly turning pale. Grimacing in pain, the man pushed back his chair with a struggle and staggered to his feet. With little control, he stumbled a few steps before being caught in the outstretched arms of the barman.
"I've got you," Isac reassured him, as the stranger leaned heavily against him. After a few seconds, the stranger's breathing gradually recovered. Isac allowed himself to relax his hold, and after a few moments the man stood once again on his own two feet.
"Thanks," the man said. "You know, for a moment there I thought I was finally done for, and I mean finally."
"What's wrong?" Isac asked.
"No idea, it felt like someone was trying to drag me half way across the galaxy by my heart. Seems to be gone now though." He raised his eyebrows and grinned. 'Weird, eh?'
"Sit down and I'll grab you a drink, mister..."
"It's Captain actually, Captain Jack Harkness." The man turned round and smiled mischievously, the colour rapidly returning to his face. "And who, might I add, are you?"