Time Lords as a species didn't require much sleep, the Doctor less the most, but when he did sleep it was a deep and satisfying sleep. He woke with a wide yawn, stretched, yawned again and looked down, and found himself staring at a pair of breasts.
Oh.
It wasn't that they weren't perfectly nice breasts, it was just that he couldn't remember how he'd come to acquire them. Okay, nothing to worry about, it must just be a touch of regeneration amnesia, it happened to every Time Lord. All he had to do was concentrate and he was sure everything would come flooding back.
So yesterday they'd had breakfast, he'd set the TARDIS on course for London 2008 and possibly made a tiny bit of a navigational error because he and Donna had arrived on Bellias III-
The Doctor's train of thought trailed off while he was distracted by a lock of his own hair. He was ginger this time, brilliant!
Right, so Bellias III, they'd stumbled across a plot by the church to overthrow the democratically elected leaders of the planet, they'd foiled it brilliantly as per usual. Then he'd brought the body-swapping machine the rebels had been planning to use to take over the presidents body back to the TARDIS for safekeeping.
Oh, body-swapping machine, right.
The Doctor was very clever, a genius even if he did say so himself. But when he'd woken up in a female body with red hair and only one heart the morning after messing about with an alien body-swapping machine his mind had shied away from the obvious conclusion out of self preservation.
"What the bloody hell is going on here?!" the voice was male, but the tone could only belong to a thirty something woman who had spent the past few months of her life being carted around the universe by a mad alien and was quite frankly sick of things like this happening. It was the sound of Donna reaching the obvious conclusion.
The Doctor stumbled out of Donna's bedroom, still wearing her pink pyjamas and found Donna standing in the corridor pointing his own finger menacingly at him.
"You get out of my body this instant!"
"And how exactly do you suggest I do that?" The Doctor enjoyed the use of Donna's vocal chords; her voice had that sort of sneering tone that was appropriate for situations like this.
"You're the one that did this."
"It wasn't me. It was that machine, come on, there must be a reverse button on it or something." The Doctor walked in the direction of console room thinking that if the universe had any gratitude at all for all the things he'd done for it then there would be a reverse button on the body-swapping machine.
There wasn't a reverse button.
"Ah," said the Doctor.
"Oh, what now?" said Donna, lending the Doctor's voice a whiny note that he hadn't known it was capable of.
"There isn't a reversal circuit."
"You'd better think of something because I've got no intention of spending the rest of my life trapped in this stupid skinny body that's probably going to end up crushed under the weight of its own hair."
"Well," replied the Doctor, who was as unhappy about this as Donna, albeit less vocally so. "I've got no intention of spending the rest of my life in this body which…"
"Which what?" Donna said dangerously.
"Nothing," backtracked the Doctor quickly, "it's a very nice body. I've always said so."
"You've been looking!"
"No. Look, matter at hand, Donna. We're stuck in each others bodies until I can figure out a way to reverse it and… Hang on; there must be a way to rewire this thing to… Oh."
"Oh?"
"It's been running constantly for days, the battery's flat."
"I used to have a car that happened to. So much for advanced alien technology, Spaceman."
The Doctor considered pointing out that he was currently both human and a woman but he didn't think Donna would really appreciate it. "It's alright; we can recharge it off the TARDIS." He dashed around the console, pressing buttons and twisting dials. It took him several moments to realise that the reason the TARDIS seemed more unresponsive than usual was that nothing at all was happening.
"Ah."
"Will you stop bloody saying that," said Donna who had hopped up onto the jump seat and was trying to arrange the Doctor's hair so that it didn't poke her in the eye.
"The console controls, they're programmed to only respond to my genetic code, which is currently your genetic code."
"Why didn't you ever program it to work for me?"
"I thought you might go around pressing buttons. Anyway, come over here, I need you to press some buttons."
Donna hopped gingerly off the jump seat. In the Doctor's body she looked a bit like a fawn who hadn't quite grasped the basics of walking yet. "How do you manage to stay upright in this thing?"
"I could say the same thing about yours."
"What's wrong with my body?"
"It's a bit," the Doctor said vaguely, "top heavy."
"Well," Donna sniffed, "let's get this thing hooked up and I can have it back."
Donna reconfigured the TARDIS controls in accordance with the Doctor's very specific, sometimes bordering on the hysterical, instructions. Now it was just a matter of connecting the body-swap machine to the TARDIS, which should have been a pretty quick job but Donna, being Donna, kept offering her opinions.
"God, no wonder you're so skinny there's hardly any room down here." They'd had to pull up several of the floor plates to connect the machine and Donna was submerged in the console with the Doctor shouting instructions down to her.
"Why's there a spoon down here?" she asked.
"That's not a spoon," the Doctor insisted. "That's a zyton crystal converter."
"No, it's definitely a spoon. There's still milk on it, that's disgusting. Have you been using it to stir tea?"
The Doctor sighed in relief as lights on the body-swap machine started blinking. "That's it hooked up, you can come out now."
Donna struggled out of the mass of circuitry that lifting the floor panels had exposed. "How long will it take for that thing to charge up so we can get our own bodies back?"
The Doctor looked down and muttered his answer, thankfully Donna's cleavage was good at absorbing sound and she didn't seem to hear.
"What?"
"Three weeks."
"What!"
The Doctor risked looking up and found himself on the receiving end of his own Oncoming Storm stare. Were his eyes always that squinty? No wonder no one ever listened to him.
He backed quickly out of the console room. "Oi!" called Donna, "where are you going?"
"I'm going to get dressed, unless you want me wearing your jammies all day."
"Don't you dare look while you change!"
By the third day Donna was really starting to warm to her chosen subject, that subject being the inherent stupidity of body-swapping machines.
"And what sort of idiot invented it in the first place?"
The Doctor was leaning against the kitchen wall drinking a cup of tea. He had drunk a lot of tea over the last few days. Donna's body always seemed to want something: tea, toast, wine, ham sandwiches, and especially sleep. This body seemed to need an obscene amount of sleep, eight hours out of every twenty four. How the woman ever found time to get anything done the Doctor would never know.
Donna was still talking. "And what was it for? I mean what sort of sensible purpose could a machine that swaps peoples bodies possible have?"
"It depends. On Araxis they're used as a punishment, violent criminals are forced into the bodies of their victims. During the reign of Havah the benevolent they were used for medical purposes, and during the third great and bountiful human empire they're used for sex therapy-"
"What therapy?"
"Sex therapy. You know, walking a mile in your partner's shoes, finding out their likes, their dislikes."
"We're certainly not doing that."
"No. No, course not, I wouldn't dream of suggesting it. Although if we are going to be stuck on the TARDIS for weeks…" he trailed off hopefully.
Donna raised his own eyebrow at him.
"No, thought not," he changed the subject quickly. "Do you want a cup of tea?"
"No," Donna said vehemently.
"When did you go off tea?"
"I'm not drinking anything. I don't want to have to…" Donna trailed off, looking down at the Doctor's crotch.
"You mean you haven't been to the toilet in three days."
"No, thank God."
"Donna, drink some water, right now. You're going to do me some kind of serious injury."
On the fourth day the Doctor got bored. "Donna!"
"What?" Donna asked, wandering into the console room.
"I need you to press the dematerialisation button so we can land."
"I thought we were going to stay here until the body-swap machine was charged up."
"We were but I'm bored so now we're not."
"There's no chance that I'm going outside looking like this."
"You can wear my other suit if you're that worried about it."
"Yeah, not really what I meant."
The Doctor decided to blame his current predicament on Donna not following his materialisation instructions exactly. It might be technically more accurate to blame it on the aliens who'd tied him to this stake and were very keen on sacrificing him to their fertility God, but he was currently feeling a certain amount of animosity towards Donna.
Of course if he'd had the sonic screwdriver he could have freed himself in moments. Unfortunately the sonic screwdriver was in the pocket of his brown overcoat and as he was currently both the wrong height and shape for that coat Donna was wearing it. Hence the animosity.
Luckily just as they were about to get to the actual sacrificing Donna turned up, waved the sonic screwdriver around, made some frankly ridiculous sounding threats and made the aliens untie him.
Despite this the Doctor did not show the level of gratitude that Donna felt she could reasonably expect. As they made their way back to the TARDIS he said, "You can't go waving the sonic screwdriver about, anything could have happened, you could have blown my arm off!"
Donna was still feeling quite smug about saving the Doctor's life. The Doctor did not approve of this, it didn't matter what body she was in Donna was insufferable when she was smug.
"If you're that bothered about it," she said, "why don't you carry the sonic screwdriver?"
"Because in this body I've got nowhere to keep it, don't you own any clothes with pockets?"
"I could give you a handbag?"
"Donna, we've been through this. I am the last of the powerful and noble race of Time Lords, and I refuse to carry a handbag."
"Suit yourself; are you opening the TARDIS door or what?"
"The keys are in your pocket."
The one thing Donna really hated about the Doctor's body, other than the vague worry that she might accidentally snap one of his scrawny bones, was that it never slept. And the Doctor, in her body, did.
Tonight she was amusing herself by playing with the Doctor's hair in front of the bathroom mirror. She was using his gel to style his hair into a pair of devil horns when her pocket started ringing, it was that mobile the Doctor always carried around.
With a final tug at the Doctor's hair Donna flipped the phone open, "Hello."
"Doctor, its Martha-"
"This is Donna."
"Are you sure? Because it sounds a lot like you, Doctor."
"No, it's definitely Donna. We've had a bit of an accident here."
"Was it another body-swap machine?"
"Oh, my God. How many of those things are there?"
"More than you'd expect. One fell through the rift in Oxfordshire last year and UNIT got our hands on it. Total havoc broke out; it took us weeks to get everyone back into the right bodies."
"Well, Martian Boy, genius that he is, says that it's another two weeks before he can fix us."
"How's he taking it, the Doctor?"
"Whinging."
"And you're not?"
"Yeah, but I'm stuck in his body. I've got more to whinge about. Look do you want to talk to him?"
"Actually now that you mention it…"
Donna walked into her bedroom; she heaved one of the Doctor's trainers at the slumbering form on the bed. She was careful to avoid the head; the last thing she wanted was to get her own body back with a self inflicted black eye.
The Doctor sat up bleary eyed, he seemed to have developed an odd fondness for Donna's pink pyjamas, "Whu-?"
"Martha rang; she wants us back on Earth. I need you to get up and tell me what buttons to press on the console." Donna started to head out of the room then turned back, "And find somewhere else to sleep, would you. I mean you walking around wearing my body is one thing, but sleeping in my bedroom is just weird."
"Donna?"
"Yeah?"
"What have you done to my hair?"
Donna realised that the Doctor's hair was still gelled into devil horns, "I was bored."
Martha had called the Doctor and Donna back to Earth to help with the ongoing alien invasion, unfortunately their preoccupation with their current predicament rendered them worse than useless.
"The clothes," the Doctor had complained when he was supposed to be helping Martha in the lab. "The woman owns nothing with pockets. How am I supposed to save the world without pockets, eh?"
"His hair's about an inch from developing an intelligence of its own," Donna had bitched to Martha when she was supposed to be helping set up barricades around UNIT HQ.
"When I get back to my own body I'm going to buy her a better bra," the Doctor said. "It's impossible to run with these things."
"He's only got the two suits," said Donna. "When I get my body back I'm going to burn them."
"Actually," said Martha eventually, "I think we've got this invasion under control, you two can get off if you like."
"I thought you said you didn't fancy Martha?" Donna asked once they were back in the TARDIS and the Doctor was checking how close the body-swap machine was to being fully charged.
"I don't."
"Yeah, right, I'm in your body remember, Sunshine? And a certain part of your anatomy certainly fancies her. And, by the way, I want out of this body before that happens again."
"That never happened to me," the Doctor lied smoothly. "Maybe it's you that fancies Martha?"
Donna shrugged the Doctor's shoulders, "I could do worse."
"Hang on…"
"Ow!"
"Have you got the sonic screwdriver?"
"It's-"
"I can't bend very well in this body."
"Careful!"
"It's pitch black, I can't see anything."
"Will you kindly move your hand off my breast?"
"That's my breast, Spaceman."
"I'm Donna and that's the Doctor," Donna introduced them calmly. After the last couple of weeks coming face to face with an armed soldier was nothing.
"Sorry, sir," said the soldier, "but isn't Donna a woman's name?"
"No, sorry," interjected the Doctor smoothly. "Our mistake, it's the other way round. I'm Donna and he's the Doctor."
"Either way, ma'am, you're both going to have to come with me."
"Hang on," hissed Donna. "Why am I suddenly pretending to be you? You went mad when I tried that to get us out of those dungeons yesterday."
"Yes, but this is England in 1975. I know people here. I don't want them thinking I'm going to go around regenerating into you."
"You're all charm, you are. I can see why all those women before me left you."
The private who was escorting the two intruders to the Brigadier's office considered himself an enlightened 1970s guy but that still struck him as a pretty odd thing for a man to be saying to a woman.
Three weeks, two days, five hours and forty seven minutes after it had first switched the Doctor and Donna the body-swapping machine was finally charged and could switch them back.
"Ah," the Doctor sighed in relief and stretched until he could hear vertebrae pop. Donna's posture was awful; it had done terrible things to his spine.
Donna was busy inspecting herself for new alien bits, thankfully there didn't appear to be any. They looked at each other awkwardly.
"So," said Donna, "I'm going to go and shower. You know, a lot."
"Right, yeah. I'm going to stay here and reduce the body-swapping machine to its three million separate components, then I'm going to shoot them into a black hole."
"Sounds like a plan." Donna shuffled awkwardly towards the interior of the TARDIS.
"Donna?"
"Yeah?"
"The last few weeks, it's not going to make things complicated is it?"
"Not if we never mention it again, it isn't."
"Yes, excellent, brilliant. Enjoy your shower and I'll call you when we've landed."