A/N: Bonjour! Now I know that a lot of you wanted (and were expecting) some Doctor/Fred/Master romance in this chapter but I hate to break it to you...there is none! BUT I will be publishing a separate one-shot as a missing scene between the end of this chapter and the beginning of the next. I hope that satisfies all you romance lovers! I'm about of third of the way through the one-shot now so it shouldn't be too long. It'll be called "Mind Swap". Anyway, thanks to all who commented on the last chapter:

Simpa007, MayFairy, Rwyf-Yn-y-Blaidd-Drwg, Shifuni, padmay97, alyssa love, Kellie, D0ctor and Brownbug.

A Secret Swap

"Are you sure this'll work?" The Doctor asked the Master in hushed tones, conscious of the three humans asleep in the rooms close to them.

"No, but that's the fun surely?" The Master pulled the top off the phial and poured its contents into two small cups. There was barely enough in each to cover the bottom.

"So we just drink this and we'll be each other?"

The Master nodded, took a deep breath in and said, "Come on then. One, two, three..."

"Geronimo!" The Doctor stage-whispered and they both downed the contents of the cups. He winced; he could feel it sliding down his throat, ice cold before it exploded through his body. It felt like it was pulling, like it was trying to tear something out of him. He groaned and fell to his knees, through his watering eyes, he saw the Master fall too.

Then, as soon as it had begun, it stopped. The Doctor opened his eyes and stood. He didn't feel any different. Except...he was now suddenly the other side of the room and staring at the door. He turned to the Master and saw...himself. Now, that was an odd feeling.

The Master grinned and the Doctor realised that it just didn't look right on his face.

"Are we clear on the plan?" The Master said with the Doctor's voice. "You distract them long enough for me to get down there and disable whatever that panel is and we'll back here outside the rooms. Got it?"

"How long do you need?"

"Not too long...I'm a genius remember?" The Master-Doctor winked and led the way out into the dark corridor.

Walking was different in the Master's body, the Doctor realised. He was quite...ploddy. He frowned. Ploddy? Where had he got that from? Suddenly, it hit him. Fred had said it once. He chuckled to himself a little sadly. He had such good memories with her.

"Right." The Master-Doctor appeared next to him. "Lead them as far away from me as possible; I don't want any coming into the basement by accident."

The Doctor-Master nodded and they both set off in opposite directions. His head felt odd; heavier and more compact. And, for the time being, he was blonde of course. It had been a while since he was blonde, he realised as he strolled down the corridor, looking out for Clockworks to lead astray.

He sighed and was about to double back down the corridor when he heard a familiar tick tock around the next corner. He walked a little louder, trying to lure the robot out. Sure enough, it creaked around the corner and outstretched its arm, ready make the Doctor-Master his brother.

The Doctor tried not to let too much relief show on the Master's face as he realised that the robots were indeed fooled by the mind swapping device. Instead, he set off back the way he came, leading the robot down the stairs and onto the level below where two more began following. The Doctor picked up the pace to a light jog, beginning to feel the pressure. As he ducked under the arm of another Clockwork, he noticed something small, black and flashing on the wall. He only managed to get a glimpse before he had to rush off again, seven robots now fast approaching him. Surely that was most of them? He rounded a corner and rushed along another corridor, the Clockworks creaking closer and closer.

The door of the basement creaked open and the Master stumbled in, not used to the Doctor's lanky legs. He peered around the dark room, bitterly marvelling at the Doctor's good eyesight. Seeing no Clockworks in the room, he made for the sleek panel behind the TARDIS. He took in all of the buttons and levers before quickly working out how to operate it. The Clockworks had done a good job with it but it was no match for the Master's mind.

Flicking two switches, jabbing two buttons and pulling a lever underneath, the panel powered down. He turned, away from it; his work done and was met by a robot. It began raising his arm but the Master said, "You do not harm me."

It hesitated, as though considering his words, before it lowered its arm and turned away from him. The Master smirked and watched it leave. The door creaked closed behind it and the Master edged forward, running the Doctor's hand along the wooden exterior of the TARDIS. He stood in it, studied it and – with a feral grin that didn't suit the Doctor's boyish face – pushed open the door.

The Doctor puffed and panted; the Master's lungs weren't as strong as his and he was having difficulty. He raced up the stairs as quick as he could, taking them two at time with the Master's considerably shorter legs. They did have more power though, that he did have to admit. He glanced behind him and saw that robots made no attempt to follow him; as if they knew the game was over. He lurched onto the landing where he saw his own body stood leaning against the wall and watching the Master's body struggle for breath.

"You alright there, Doctor? Hope you didn't run my body too ragged."

The Doctor wheezed, "Well...when we swap back...you...you might be feeling rather achy."

"Oh, great."

"What happens now?" The Doctor asked, hands on his knees as he bent double. "Did everything go to plan?"

"Oh yes. Easy. The panel's shut down so we'll have to see in the morning how it's affected the robots."

The Doctor stood up straight. "When will we swap back?"

"No idea. Sometime before morning I expect. In the meantime, I suggest we sleep this off. In the morning, no one will know anything about it." The Master said, using the Doctor's voice. The Doctor watched his own body wander off towards the room he'd been given. "This is your room, isn't it?"

The Doctor huffed. "I don't want you going in my room!"

The Master rolled the Doctor's eyes. "If I don't, it'll look pretty strange if we come out of each other's rooms in the morning, won't it? We'll change back soon, thankfully. Trust me; I don't want to be stuck in your gangly body for any longer than I have to. Just rest and stop whining." And with that, he entered his room and slammed the door shut, leaving the Doctor in the dark corridor.

So it worked! But what are those things on the walls? And what was the Master up to in the TARDIS? Hmmm...

I hope that chapter didn't disappoint and please do look out for this chapter's missing scene one-shot coming up called "Mind Swap"!

Please review!