Zoe watched in fascination as Jamie tried to find a position in the armchair that was both comfortable and wouldn't have her sliding down the velvet into a heap on the floor in the middle of the night. "Are you seriously planning to sleep there all night?"

"Aye," Jamie grunted, clinging to the chair for dear life as she felt herself slipping over the edge. Was this thing actually a chair, she wondered? Or did Zoe's body just have an oddly shaped bottom?

"Oh Jamie, you're being ridiculous," the girl in Jamie's body scolded. He patted the empty space next to him. "There's plenty of space here. Or you could always try sleeping on the sofa in the Doctor's room," he suggested as Jamie glared at him.

"No way," Jamie said firmly, wriggling back another inch. "I know you, as soon as my back's turned, you'll be doing something weird with my body in the name of science."

Zoe groaned and let his head flop back onto the pillow with a thump. "You're so frustrating!" he complained. "It's all right for you, you've been a girl once before-"

"That was-" Jamie began, outraged, and promptly slid off the chair onto the floor in a heap of heavy silk and velvet blanketing.

"-But this could be my one chance to experience life as a man and you won't even let me pee in peace because you're afraid I'm going to laugh at your willy or something!"

Jamie disentangled herself from the piles of slippery fabric and stood up furiously. "Well, if we ever find another terraforming machine, I'll gladly turn you into a laddie for as long as you like, but right now you're in my body, not yours, and it's nae a science project."

At that moment, the Doctor poked his head around the door frame. "Everything all right?" he asked mildly, looking at his two companions. "I heard raised voices."

"I'm fine," Jamie muttered, evidently giving the chair up as a lost cause as she began to rearrange the blankets on the floor.

The Doctor looked pointedly at Zoe, who threw his hands into the air in surrender. "Oh all right," he said ungraciously. "I'll leave Jamie's body alone."

"Wonderful, glad to hear it. Now sleep well, we've got a busy day tomorrow." And with that, the Doctor clicked his fingers to activate the light switch, and closed the door.

There were a few seconds of silence before Zoe spoke. "How do you cope with all this hair on your legs? I'm getting friction burns."

"Well you've got a funny-shaped bottom," Jamie replied sulkily.

"I do not!" Zoe gasped.

"Go to sleep!" the Doctor shouted from the other room.

There were a few more seconds of silence before Zoe spoke up once more. "I'll have you know, I have a lovely bottom. That bottom's had fan mail."

Next morning, the trio awoke bright and early and made their way to the fifth floor conference room. "Well, here we are," the Doctor said cheerfully, turning to face his two companions in their colourful robes. "Fingers crossed the real Doctor Jones hasn't shown up yet, hmm?" And with that, he strode towards the man standing outside the door. "Doctor Jones and guests for the SMATA conference."

"Yep, fine, in you go," the man said, checking the name off a clipboard.

The Doctor grinned. "After you two," he said, holding the door open.

The man didn't even look up as he stuck an arm out to bar Jamie's way. "Not you."

"Ah." The Doctor sighed as Jamie folded her arms stubbornly. "Jamie, perhaps you'd better go and wait in our suite. We'll come and get you when we're ready."

"Och, but Doctor-" Jamie protested.

"It'll be much more convenient than trying to track you down in jail," he added quietly.

Jamie considered the wisdom of this for a moment and then with a snort of exasperation, she stomped off down the corridor, muttering obscenities under her breath.

"Oh dear," Zoe commented. "I think I'd like our chances better if Jamie and I were in the same place."

"I quite agree. Still, maybe it's for the best," the Doctor said, looking around the rows of chairs for a suitable place to sit. "He would've been terribly bored."

After several minutes, Jamie poked her head cautiously around the corner of the hallway.

The man with the clipboard didn't look up as he called, "I know you're there. Go back to your suite, or I'll call security."

"Och, I'm going," Jamie snapped. She stomped down the hallway, moodily kicking at the wall as she went.

"Oi, girl!" an outraged voice shouted. "What do you think you're doing!?"

Startled out of her sulk, Jamie took one look at the angry man striding towards her and sprinted in the other direction.

The plimsoles had been a wise investment and Jamie was easily able to outrun her pursuer. Several minutes later, she skidded into the lobby, hurriedly sat down on a chair and pretended to read a magazine. After several minutes had passed without anyone shouting or yelling, she dared peek over the top.

The lobby was beginning to fill up with people walking to and from the restaurants. Jamie's stomach rumbled as she recalled that none of them had had any breakfast, as the Doctor had been eager to get to the conference before the real Doctor Jones turned up. Perhaps she could go and get some food. She might run into Kerria. Kerria, whose husband was the head of the research committee.

Kerria was indeed in the mixed restaurant, eating something blue and lumpy and she greeted the other girl with a wave. "Good morning, Jamie. Did the Doctor and Zoe get into the conference successfully?"

"Aye. They wouldnae let me in though," she added, and narrowed her eyes at the other girl. "I don't suppose you could get me in, could you?"

Kerria started laughing. "Oh, sorry, were you serious?" she asked as Jamie glared at her. "I can't even get myself in there!"

"Well as close as possible then," Jamie amended. "I want to be near when Zoe and the Doctor are ready."

Kerria steepled her fingers thoughtfully. "All right," she finally said. "I'd quite like to know what's going on in that room too. Our suite is on the fifth floor, let's go there and make a plan."

"This here is the conference room," Kerria said, pointing to a room on her sketch. "These two rooms here are smaller meeting rooms that are generally used to store supplies during these events. My husband, Tarrent, uses one for administration."

"What's that wee room there?" Jamie asked, pointing to a small room next to the meeting rooms.

"That's a linen cupboard," Kerria confirmed. "If we could get in there, there may be a vent or something we could watch through. But it'll be locked."

"Aye, well..." Jamie lifted the hem of her robe up and pulled her knife out of her sock. "I've brought my own key," she said smugly.

Kerria grinned. "That should do nicely."

The two girls opened the door and peered out into the corridor. The conference was now in full swing and the hallway was deserted. They tiptoed quietly towards the conference room and stopped at the last door before it. "This is it," Kerria whispered, flattening herself against the wall and nodding at the doorframe.

Jamie had another quick look around, noting that the corridor was indeed deserted, which was very fortunate because they were completely conspicuous. Crossing her fingers in hope that the lock didn't have some sort of weird, futuristic alarm, she stuck the knife between the door and the frame and quickly jimmied it open.

It was immediately clear that the hotel housekeeping staff had had the same idea at some point in the past. High trolleys filled with blankets, pillows and towels filled much of the room, but a space had been made for a comfortable-looking chair, which sat directly in front of a grating set into the wall. Kerria immediately knelt on the chair to peer through the grating into the room beyond. "This is perfect!" she hissed, beckoning Jamie over. "Look, that's Tarrent."

Jamie closed the door behind them, and rearranged some of the trolleys to form a screen in case anyone else entered before joining the other girl. "Him up on the stage?" she asked. Kerria nodded. "Can ye see Zoe and the Doctor anywhere?"

"Over there, on the other side of the room."

They watched silently for a while longer, and then Jamie spoke. "So... what are they doing?"

"Representatives from various scientific, technical and mathematical groups will present their projects and papers before the committee," Kerria explained. "And the committee will vote on any issues that arise."

Jamie looked around the crowded room. "And... will they all be presenting stuff?" she asked slowly.

"Most of them, yes."

Jamie groaned. "Och, that could take hours!"

Kerria looked confused. "Well, yes. These things generally do. What's the problem? I thought you wanted to watch?"

"Oh aye, I do, I do," Jamie said hastily. "I was just... more interested in the science things than the others. I wish I'd brought a book," she added, thinking wistfully of the Harry Potter book sitting on her bedside table in the TARDIS. She'd been slowly making her way through all ten books ever since the Doctor had taught her to read, but as they were all forbidden to remove books from the TARDIS (the picnic had been a special occasion and even then, she guiltily remembered that they'd almost left the books behind), it was slow going.

"You can read too?" Kerria asked, looking impressed. "I like to read, but I'm not very good at it."

"Me neither," Jamie admitted. "I drive Zoe mad, reading. She's read nearly everything else on the TARDIS and keeps pestering me t'read faster."

"TARDIS?" Kerria asked, confused. Then she frowned. "She?"

Oops. "He! He, of course, Zoe's no' a lassie," Jamie said quickly. "Ha ha. That would be silly."

Kerria narrowed her eyes.

"The TARDIS is our space craft," Jamie said brightly in an attempt to change the subject.

"Space craft?" Kerria asked. "You can't be an astronaut, you're a girl. Or Zoe's a girl. One of you is a girl."

"It's the Doctor's space craft and he doesnae care about that. And I'm the girl," she added belatedly. "Of course. Always have been, ever since I were a wee bairn-oh what's the use?" she sighed. Kerria clearly wasn't falling for it. "Zoe's the girl."

Kerria looked back through the vent in awe. "That's amazing! A girl is in there, right now, and not a single one of them knows! Well, apart from the Doctor," she corrected herself. "How did this happen?"

"Zoe happened," Jamie said with a wry smile. "She's a nosy lass. We snuck into the Science City and she put this helmet-thingy on our heads and the next thing we know, we're no' ourselves anymore."

"And this helmet-thingy has been brought here for the conference," Kerria said, understanding dawning upon her. "That's why you're here, isn't it?"

"Aye," Jamie nodded. "I wasnae expecting it to take hours and hours though."

The two of them watched the conference is silence for several minutes as a man stood up to report that his research team had found a new kind of catalyst to break down gloop.

"You know, you're doing very well at being a girl," Kerria said eventually. "I was completely fooled."

"I've had practice," Jamie admitted.

"Hmm." Kerria continued to watch the events in the other room. "I wonder if they ever considered that the machine could be used in such a way, to swap the minds of a man and a woman?"

Jamie shrugged. "They will once the Doctor's had a chat with them."

The Doctor lolled back on his chair, utterly bored. He'd spent the first fifteen minutes of the conference pointing every flaw in every presentation under his breath to Zoe, only for the boy to turn and threaten to turn him in as a gatecrasher if he didn't shut up. There hadn't even been any excitement when the real Doctor Jones arrived; the man on the door had simply shrugged and let him in. Admittedly it was for the best, his companions needed to switch back as soon as possible, but listening to out-of-date science in silence wasn't his idea of a good time.

He harrumphed loudly as a mathematician finished giving a (completely wrong) talk about yarn theory and then winced as Zoe elbowed him sharply in the ribs. "Do be quiet, Doctor, you'll get us thrown out!"

"Well, they're all wrong!" he protested as quietly as possible.

"I know they're all wrong," Zoe hissed back. "But can't you just daydream quietly instead of getting all huffy about it?"

"I could," the Doctor muttered petulantly. "If I wanted to."

Suddenly Zoe sat up straighter and elbowed him in the ribs again. "Doctor!"

"I didn't do anything!"

Zoe rolled his eyes and nodded at the man who'd just stood up with a helmet in his hands. "That's it, that's the PED," he hissed. "Now what do we do?"

"Now?" The Doctor sat up straight and a serious expression appeared on his usually humorous face. "We wait."

"That's it, that's the thing that switched us!" Jamie exclaimed. Kerria pressed her nose against the grating to get a better look. "You see? Two people wear the helmets and that control box switches their minds."

"How extraordinary," Kerria murmured. "Oh dear. They don't like it."

Indeed, in the room beyond, raised voices could be heard as the scientist with the PED began arguing with the man Kerria had identified as her husband, Tarrent. Jamie watched with growing unease as Tarrent lectured the scientist about "failing to grasp the inherent dangers of such a device falling into the wrong hands."

"Imagine, with that device, you'd never know who you were really talking to," Kerria said thoughtfully.

"Shh," Jamie whispered, trying to concentrate on the argument. As she watched, the scientist sullenly sat down, his presentation over. "Now what happens?"

"I imagine once the Doctor and Zoe have explained your problem, the device will be sent back to the Science City to be dismantled," Kerria said. "For now, we'll just have to wait."

It was at least two hours later when Kerria finally tapped Jamie on the arm and told her the meeting was over. "About time too," Jamie grumbled, crawling out of an elaborate blanket fort. She joined the other girl at the grating and peeped through. Inside the conference room, the crowd was beginning to thin out. The committee was gathering up boxes and papers and as she watched, the Doctor and Zoe began to push their way forward.

And then, much to her frustration, Tarrent, Zoe and the Doctor disappeared into another room.

"What now?" Kerria asked. "Shall we wait for them to come back out."

"No..." Jamie looked thoughtfully around the room. She raised her eyes to the ceiling and smiled. "Ceiling tiles! We'll see if we can reach that there room through the ceiling."

"You're not serious, are you?" Kerria asked incredulously as Jamie began to climb up one of the shelving units.

"Och, I've crawled through vents on the moon, pipes on Skaro, lift shafts in London... Zoe once crawled halfway across a hospital through one of these," Jamie said cheerfully, pushing the ceiling tile up out of the way and hauling herself up into the space above. "It's amazing how many places you can get to in these kinds of spaces."

"-And so we need to use the PED to switch them back," the Doctor finished.

Tarrent Kline drummed his fingers against the table where the PED sat as the two strangers in front of him finished their wild tale. "So you and a young lady-"

"Young man," Zoe corrected. "I'm the lady."

"-Broke into our Science City, tampered with a piece of very delicate electronic equipment, and then gatecrahed this conference in order to regale me with your tall tale," Tarrent continued loudly.

"Tall tale?" the Doctor protested indignantly. "It happens to be true!"

"The Science City is well guarded-"

Zoe snorted. "Their windows aren't."

"-And there's no way a woman would've been able to sneak in, undetected."

"To be fair, they did spot us very quickly," Zoe murmured.

"Do you have any proof to back up your absurd story?" Tarrent asked sternly.

"Well, there's... er..." The Doctor trailed off and looked helplessly at Zoe. How on Gallifrey was someone supposed to prove something like that? He was suddenly reminded of the trouble he'd had convincing Ben and Polly he was still himself after his regeneration - and they'd been there at the time.

"I thought so," Tarrent said with satisfaction. "I know what your plot is. You're female sympathizers! You want to disguise women as men and let them take over the world! I won't stand for it. I'm calling security."

Zoe and the Doctor exchanged bemused glances, then as Tarrent turned to pick up the phone, Zoe looked around desperately for something to hit him over the head with. But before he could move, the ceiling above the man splintered and a figured crashed down on top of him with a yell. Tarrent fell to the ground, stunned.

"Jamie!" the Doctor exclaimed. "I thought I told you to wait in the suite?"

"Aye, well, I thought I'd better stay nearby, just in case," Jamie explained, scrambling to her feet.

"Good thing you did," Zoe said. "He was about to call security on us. Doctor, are you really sure this man is the prime minister who'll change laws for women?"

"Never mind my history, get these on quickly." The Doctor handed his companions the PED helmets and hopped impatiently from foot to foot as they jammed them on their heads. "Everyone ready?"

"Ready?" Zoe and Jamie confirmed.

The Doctor hit the remote. There was a blinding flash of blue light. "Oh crumbs! Is that supposed to happen?"

"It worked!" Zoe patted her body down quickly to make sure everything was in the right place and started to dance a happy little jig. "I'm me again!"

"I'm me too!" Jamie said happily. He quickly yanked the helmet off of his head before anything else could happen and tossed it onto the table.

"Wonderful, wonderful!" The Doctor clapped his hands together. "Now, I think we'd better-"

"Hello." Kerria poked her head out of the hole in the ceiling. "Could you help me down from here please?"

"Oh. Yes, of course." The Doctor looked around for a moment and then began to drag the table over. "Jamie, Zoe, could you give me a hand here?"

A few moments later, Kerria was safely back on the ground. "So you're really Zoe, not Jamie?" she asked, picking up a helmet an examining it.

Zoe opened her mouth to answer, but the Doctor interrupted. "I'm sorry to be rude, my dear, but I think we should hurry up and leave before that fellow over there wakes up." He nodded over at Tarrent, who was still lying unconscious on the floor.

"Oh yes, of course." Kerria turned the helmet over in her hands, and then, to their surprise, walked over to her husband and carefully placed it on his head. "Before you go though, could you possibly restrain me?" She smiled at their dumbstruck expressions and placed the second helmet on her own head. "It'll be far more difficult for Tarrent to undo the switch and call security."

"Oh my goodness!" the Doctor spluttered. "Well I never! We couldn't- I mean, it would be- of all the-"

Zoe suddenly let out a snort of laughter. "I think I'm beginning to understand what prompted Tarrent Kline's change of attitude. Come on, Jamie. Let's tie her up."

"Really, Zoe, this is quite absurd!" the Doctor protested weakly as his friends untied the belts from their robes and began to tie up the other girl.

"Och, Doctor, it willnae hurt the man t' be a lassie for a wee while," Jamie said with a laugh. "You all right, Kerria?"

Kerria tested her bonds. "Just fine. Perhaps they could be a little tighter?"

Just then Tarrent groaned and began to stir. Jamie and Zoe exchanged glances and then lunged for the remote. There was another flash of blue light.

Kerria - or at least, the person who looked like Kerria - looked disorientated for a moment, then suddenly sat up straighter and began to struggle against her bonds. "I say! This is completely outrageous! Switch me back at once!"

"Looks like it worked perfectly," Zoe said with satisfaction.

"Yes. Well. It's nice to see that someone here today got their science right," the Doctor grumbled.

The real Kerria sat up with a groan. The helmet slipped from his head and he looked at it in confusion for a moment before shakily climbing to his feet. "Gosh. This is a bit different."

"Kerria!" Tarrent shouted. "How dare you! Undo this!"

Kerria calmly removed the second helmet from Tarrent's head. "I suggest you three leave now," he said, glancing back over his shoulder. "I'm going to call security and inform them that my wife tried to gatecrash the conference, and I'd hate for Zoe to get into trouble."

Jamie snorted. "Aye, well, Zoe doesnae need any help doing that."

"You're one to talk!" Zoe retorted.

Before a serious argument could erupt, the Doctor took both of his companions firmly by the arm and began to lead them out of the room. "Yes, it's definitely time we left. Goodbye."

"And good luck in the elections," Zoe added cheerfully. "Whichever one of you it is."

"Wait, you can't go! Don't leave me like this!" Tarrent shouted. "You can't do this to me!"

"We really shouldn't have done that," the Doctor fretted as they began the long train journey back to the TARDIS. "It wasn't terribly nice of us."

"I wouldn't worry too much about it," Zoe said. "Once Kerria makes things better for women, she'll probably be more than happy to switch back. It's really not as much fun as I thought it would be. Especially when someone else deliberately chucks your body out of the ceiling and leaves giant bruises all over you," she finished pointedly.

"If I hadnae done that, we'd still be chasing that thing up and down t' planet," Jamie retorted.

"Never mind," the Doctor interrupted quickly. "The important thing is, we're all back to normal and now we can- oh no! Oh my word!"

"Doctor, whatever's the matter?" Zoe asked, concerned.

The Doctor groaned and raised a hand to his face in frustration. "I've left the mercury back in our hotel suite."

AN: Wow, has it really been six years since I started writing this fic?

*checks*

Yes, it really has. I've got no excuses because I can't actually remember why I stopped. Looking at the dates, it could be I moved house? I don't know. I really don't. Point is, I stopped for a long time. And then last month, something amazing happened – they found nine missing Troughton episodes. Enemy Of The World and Web Of Fear went from having one episode each to complete/one episode missing. I immediately gorged myself on them. And then I decided I wanted to reread all the Target novels to refresh my memory of the Troughton era. Then I got fed up of waiting for my uncle to buy me The Ice Warriors for my birthday and went ahead and brought it myself. And then I replaced my VHS copy of The Mind Robber with a DVD. And then I rewatched all the other ones I owned. And my brain was full of IDEAS. But I remembered this poor, neglected, forgotten old fic and decided that before I would allow myself to start a new one, I would jolly well finish this one first.

So that's what I did.