A/N: So I sort of designed the room that John is stuck in as I imagine the Zero Room in the TARDIS looks like. It's only used once or twice in Classic Who, and where John is isn't really the Zero Room, but yeah. You get the picture.

The Ol' Switcheroo

"That's very kind," Hame said as the Wolf handed her the cup of water she had fetched. "There's no need."

"You're the one working," the Wolf pointed out.

Hame shrugged. "There's not much to do, just maintain his smoke. And I suppose I'm company." She smiled a bit. "I can hear him singing, sometimes, in my mind. Such ancient songs," Hame said in wonder.

"Am I the only visitor?" the Wolf asked.

"The rest of Boe-kind became extinct long ago. He's the only one left. Legend says that the Face of Boe has watched the universe grow old. There's all sorts of superstitions around him," Hame explained. "One story says that just before his death, the Face of Boe will impart his great secret, that he will speak those words only to one like himself."

The Wolf looked over at the novice, curious. "What does that mean?"

Hame shook her head. "It's just a story," she replied, embarrassed at her folly.

"Tell me the rest," the Wolf urged gently.

"It's said he'll talk to a wanderer. To the woman without a home. The lonely Goddess," Hame said quietly. The Wolf's eyes widened in surprise.

John stared at his surroundings, trying to figure out what the hell had happened to him. Had Cassandra transported him somewhere? The room he was in was white and completely empty. There were no windows, no doors, not a single decoration. He couldn't even tell where the floor ended and the walls began.

He walked forward, but was met suddenly by a barrier not ten feet in front of him. He kept his fingers on the wall and explored his container. It wasn't large by any means, and he quickly had the whole room scoped out. He was distracted from his perusal by an image flickering into existence on the far wall. It displayed like a projector, but it came out of nowhere.

John stared at the 'screen', for lack of a better term. He could see Chip, but it was like he was seeing him using another person's eyes.

"Moisturize me," a familiar voice ordered.

"No way," John muttered. "No. No, just – no." But he couldn't deny the truth when the screen turned to a mirror, showing himself. "No, come on!" John shouted angrily. "That's not fair! That's my body! You can't just take my body, Cassandra!"

"How bizarre," Cassandra said, as John. "Arms, fingers, hair! Ooh, big hair." She stared at the mirror, admiring her new body. "Oh, well, this is – different. Goodness me, I'm a man. Yum. So many parts," she mused, feeling around.

John made a disgusted noise.

"Ooh, he's slim. And a little bit foxy," Cassandra said with approval.

"Oh, the brain lead expired," Chip mourned. "My old Mistress is gone."

"But safe and sound in here," Cassandra reassured him, tapping on John's head.

"But what of the John child's mind?" Chip asked.

"Yes, what of him?" John muttered sardonically.

"Oh, tucked away," Cassandra dismissed. "I should be able to just about access the surface memory –" she growled in frustration. "Where is it?"

"Mistress?"

"The little rat is hiding his memories. How is he doing that?" Cassandra huffed, frustrated.

"Ha!" John crowed.

"John Smythe was with a woman earlier," Chip pointed out after a moment.

"No, no, you leave her alone!" John shouted, not noticing that the walls had encroached on him by a miniscule amount.

"Yes, she should have the answers. I'm surprised he's not with the Wolf. That hypocrite, chasing after any old blonde chav. They seemed thick as thieves." Cassandra was interrupted by John's super phone ringing in his coat pocket. Cassandra pulled it out, staring at it in consternation. "Oh. It seems to be ringing. Is it meant to ring?" she asked Chip.

"A primitive communications device," Chip suggested. Cassandra shrugged and flipped it open.

"John, where are you?" the Wolf asked.

Cassandra covered the phone. "How does he speak?" she hissed at Chip.

"Old Earth Estuary. Or is it Cockney?" Chip replied, puzzled.

She put the phone back to her ear. "Er, righto," she tried.

"Huh?!" John cursed, running his hands through his hair frustratedly.

"Where've you been?" the Wolf asked. "How long does it take to get to Ward 26?"

"Apparently too long, since I'm not there," John muttered. "Maybe that's weird, Wolf."

"I'm on my way, governor," Cassandra said instead. "I shall proceed up the apples and pears."

"That is not how I talk!" John yelled. "Surely you can see that, Wolf."

"You'll never guess," the Wolf went on, seemingly undisturbed. "I'm with the Face of Boe. Remember him?"

Apparently, she can't, John stewed. The walls inched closer again.

"I'd better go. See you in a minute." The Wolf hung up.

"That woman is with the Face of Boe!" Cassandra exclaimed. "But he was on Platform One. That must mean – oh, he is with the Wolf! That hypocrite! I must get the name of her surgeon. The boy could do with a little work."

"Don't you dare," John growled.

"This Wolf woman is dangerous," Chip said nervously.

"Dangerous and clever," Cassandra acceded. "I might need a mind like hers. The Sisterhood is up to something. Remember that Old Earth saying, never trust a nun? Never trust a nurse. And never trust a cat. Perfume?" Chip handed over the small bottle he had used on John. She placed it in her coat pocket.

"There you are!" the Wolf called as Cassandra exited the lift. She came over and grabbed her arm. "Come and look at this patient. Marconi's Disease. Should take years to recover. Two days," the Wolf said in disbelief. "I've never seen anything like it. They've invented a cell washing cascade. It's amazing. Their medical science is way advanced. And this one." She pulled Cassandra over to another patient.

"No, no, no, Wolf!" John yelled. "It's not me! Come on!"

"Pallindrome Pancrosis. Kills you in ten minutes, and he's fine. I need to find a terminal. I've got to see how they do this. Because if they've got the best medicine in the world, then why is it such a secret?" the Wolf wondered.

"I can't Adam and Eve it," Cassandra said.

The Wolf gave her a strange look. "What's – what's – what's with the voice?" she asked.

"Finally!" John said.

"Oh, I don't know," Cassandra drawled. "Just larking about. New Earth."

"I thought you were more excited about seeing all the medicine stuff Johnny."

"Everything's new," Cassandra mused.

The Wolf grinned. "Well, I can talk. New New Wolf.

"Mmm, aren't you just," Cassandra said before pulling the Wolf in for a long, hard kiss.

John's mouth dropped open. "Ugh!" he cried, burying his face in his hands in second-hand embarrassment for his body. "Oh, no. Oh, no no no no no."

When Cassandra let the Wolf go, she just stood there, frozen. "T-Terminal's this way," Cassandra stammered before walking away. The Wolf dumbly followed.

John began pacing, unable to watch anymore. But he was surprised to notice that the area was much smaller than it had been. He only had about ten paces of room, compared to the nearly twenty he'd begun with. The room was getting smaller, and he didn't know why.

John assumed that he was somehow trapped in his own mind. Cassandra had managed to make some kind of a transfer, or had implanted her mind in his body, kicking him out. And he found that he was very annoyed about that. But what was concerning right now was the fact that he didn't know if he could be crushed by his own mind, if that was what the walls were. Or was it Cassandra's mind, maybe?

That, and the Wolf was in danger, clueless as to what was going on. John had to somehow regain control of his body. He pounded on the walls again, screaming to be let out, but nothing happened. He searched every inch of the room, but there were no openings, no entrances, not even a tiny little crack in the facade. It was a perfect prison. Having accomplished nothing, John turned his attention back to what the Wolf and Cassandra were doing.

The Wolf was inspecting a computer terminal. "Nope, nothing odd," she said. "Surgery, post-op, nano-dentistry. No sign of a shop. They should have a shop."

"No, it's missing something else," Cassandra interjected. "When I was downstairs, those nurse cat nuns were talking about Intensive Care. Where is it?"

The Wolf gave her a considering look. "You're right. Well done," she praised cautiously.

"Why would they hide a whole department?" Cassandra went on. "It's got to be there somewhere. Search the sub-frame."

"Sub-frame," John scoffed.

"What if the sub-frame's locked?" the Wolf asked, testing her.

"Try the installation protocol," Cassandra suggested.

"Installation protocol, really?!" John shouted. "I don't know anything about computers! Doesn't that seem just a little off to you, Wolf?" Fed up, he surveyed the room again. It had decreased in size by another half pace. "Okay," he muttered to himself. "I'm trapped in my own head. Cassandra's taken over my body. I have no control. But two minds in one head can't feel good, and right now, I'm on the receiving end. But if I can still see what I'm – she's – doing, maybe the connection goes both ways," he mused. "Like the Matrix." John stalked back to a wall, and this time, when he beat his fists on it, he focused all his mental energy on forcing the sensation to Cassandra's brain. He did it again and again, and after six hits, he was rewarded when Cassandra flinched.

"Ha!" He did it again. Cassandra flinched again, but then the walls inched even closer together as she focused on blocking him out. "Damn it!" There went that plan. He couldn't risk further retaliation. He'd get squashed before the Wolf ever realized he was in danger. John moved back toward the screen, and the walls resumed their slower, but still inexorable, pace around him.

The Wolf and Cassandra were heading down a staircase. Thousands of cells lined an entire network of platforms. The Wolf opened one of them at random, revealing a very sick looking man.

"That's disgusting," Cassandra muttered. "What's wrong with him?"

"I'm sorry. I'm so sorry," the Wolf apologized softly, closing the cell and moving to the next, which contained a sick young woman.

"What disease is that?" Cassandra asked.

"All of them. Every single disease in the galaxy," the Wolf answered darkly. "They've been infected with everything."

John looked on in horror at the disease ravaged people. Who would keep them locked up like that? he wondered. They couldn't be patients. No one treated patients that way. It was inhuman.

"They're not patients," the Wolf was saying, thinking exactly what John was.

"But they're sick," Cassandra protested.

"They were born sick. They're meant to be sick. They exist to be sick. Lab rats," the Wolf snarled, disgusted. "No wonder the Sisters have got a cure for everything. They've built the ultimate research laboratory. A human farm."

"Why don't they just die?" Cassandra asked.

"Plague carriers. The last to go," the Wolf explained.

"It's for the greater cause," a soft voice said from behind them.

Cassandra and the Wolf whirled around to face the newcomer. "Novice Hame," the Wolf growled. "When you took your vows, did you agree to this?"

"The Sisterhood has sworn to help," Hame defended.

"What, by killing?" the Wolf demanded, her voice rising.

Hame smiled. "But they're not real people," she tried to explain. "They're specially grown. They have no proper existence."

"What's the turnover, hmm? Thousand a day? Thousand the next? Thousand the next? How many thousands? For how many years? How many?!" the Wolf was practically screaming by the end. John flinched, and even Cassandra cowered in the face of her anger.

"Mankind needed us," Hame insisted. "They came to this planet with so many illnesses. We couldn't cope. We did try. We tried everything. We tried using clone-meat and bio-cattle. But the results were too slow, so the Sisterhood grew its own flesh. That's all they are. Flesh," she said, trying to make the Wolf understand.

"These people are alive," the Wolf said.

"But think of those humans out there, healthy and happy, because of us."

"If they live because of this, then life is worthless," the Wolf denied.

"But who are you to decide that?" Hame asked.

"I'm the Wolf. And if you don't like it, if you want to take it to a higher authority, then there isn't one. It stops with me," the Wolf declared.

Despite his worry, John couldn't help but grin at the sight of the Wolf's expression that he now recognized as her 'Bad Wolf' face. This was her against the universe, and she would always come out on top. Most of the time, she hid that persona under a stiff mask, but when it came out, nothing could stand in her way.

But she was speaking again. John refocused. "Hold on," the Wolf said, interrupting whatever Cassandra and Novice Hame had been speaking about. "I can understand the bodies. I can understand your vows. One thing I can't understand." She pointed over at Cassandra. "What have you done to John?"

"I don't know what you mean," Hame said, now looking confused.

"Yes!" John yelled, pumping his fist in victory. She'd known all along.

"And I'm being very, very calm. You want to be aware of that. Very, very calm," the Wolf told Hame, her voice taking on a dangerous undertone. "And the only reason I'm being so very calm is that the brain is a delicate thing. Whatever you've done to John's head, I want it reversed."

"We haven't done anything," Hame denied.

"I'm perfectly fine," Cassandra added..

"These people are dying. John's a doctor, he would care," the Wolf said, her voice getting very quiet.

Cassandra sighed. "Oh, all right, clever clogs," she said, walking over to the Wolf. "Smarty-pants. Femme fatale," she practically moaned.

John groaned at the words coming out of his mouth.

The Wolf just gave her a confused look. "What's happened to you?" she whispered.

"I knew something was going on in this hospital, but I needed this body and your mind to find it out." Cassandra said.

"Who are you?" the Wolf asked.

"The last human," Cassandra whispered in her ear.

The Wolf frowned. "Cassandra?"

Cassandra rolled her eyes. "Wake up and smell the perfume," she said, annoyed, pulling out the small bottle.

"No, Wolf look ou –" John yelled, but it was pointless.

Cassandra sprayed the Wolf in the face and she promptly collapsed. After Hame ran off to find the Matron, Cassandra stooped to lift the Wolf.

"Don't you touch her," John snarled, banging on the walls with renewed vigor.

Cassandra dropped the Wolf in surprise. "Why won't you just go away?" she hissed, digging the heel of her hand into her temple. "You should be gone by now, or at least not making this much of a fuss. You're supposed to be helpless in there!" she complained as she bent over again.

"Not bloody likely," John growled, pounding again. However, Cassandra was ready that time, and managed to keep a hold of the Wolf long enough to lock her in one of the empty cells. Chip rejoined his Mistress.

"No, you can't leave her in there!" John yelled.

A few minutes later, he heard the Wolf shouting from inside the cell. "Let me out! Let me out!"

"Aren't you lucky there was a spare?" Cassandra jeered. "Standing room only."

"You've stolen John's body," the Wolf accused.

"Over the years, I've thought of a thousand ways to kill you, Wolf," Cassandra hissed. "And now, that's exactly what I've got. One thousand diseases. They pump the patients with a top-up every ten minutes. You've got about three minutes left. Enjoy."

"Just let John go, Cassandra."

John cringed at the Wolf's pleading tone. Turning away so he wouldn't have to watch the Wolf get infected, John discovered that he didn't even have room to stretch his arms anymore. Worry setting in, he pushed on the walls, bracing himself to throw his whole body weight into it. But to no avail. They didn't budge. "This is not good," he muttered. It appeared that he was running out of time.

John turned his attention back to the screen just in time to watch Chip pulling a lever that opened all the cells on their level, letting the Wolf and all the diseased people out. "What've you done?" the Wolf yelled.

"Gave the system a shot of adrenaline, just to wake them up. See you!" Cassandra took off down the stairs, the Wolf following close behind.

"Don't touch them!" the Wolf warned. "Whatever you do, don't touch!"

When they were a couple of levels down, Cassandra stopped suddenly to look back up. John saw one of the diseased touch Sister Jatt. She died screaming.

"Oh, my God," Cassandra whispered.

"What the hell have you done?" the Wolf accused.

"It wasn't me," Cassandra protested.

"One touch and you get every disease in the world, and I want that body safe, Cassandra," the Wolf threatened. "We've got to go down."

"But there's thousands of them!"

"Run! Down! Down! Go down!" the Wolf urged. The three of them sprinted down the stairs, slipping between diseased people. John winced whenever a diseased hand got close to the Wolf, breathing a sigh of relief when she escaped yet again. He could hear an announcement of a quarantine over the loudspeaker. He assumed that the escaped patients had gotten to the real patients' floors.

They finally got to the basement, and Cassandra ran to summon a lift, but the Wolf called her back. "No, the lift's have closed down. That's the quarantine. Nothing's moving."

"This way!" Cassandra ordered, running in the direction of her hideout.

Chip went to follow, but he was cut off by a swarm of escapees. "Mistress!" he wailed, but Cassandra ignored him and kept running for her lair.

"I'm sorry!" the Wolf apologized. "I can't let her escape."

Cassandra looked ready to tear out John's hair when the Wolf caught up.

The Wolf quickly inspected the machinery in the hideout, immediately realizing what it was.

John was feeling the pressure inside the room as the walls began to press against him. He was going to get crushed.

"We're trapped!" Cassandra lamented. "What am I going to do?"

The Wolf stopped in front of her, furious. "For starters, you're going to leave that body," she commanded. "That psychograft is banned on every civilized planet. You're compressing John to death!"

"Well that explains it," John muttered as the walls got even closer.

"But I've got nowhere to go. My original skin's dead," Cassandra whined.

"Not my problem," the Wolf dismissed. "You can float as atoms in the air. Now, get out," she ordered. "Give him back to me."

Cassandra smirked. "You asked for it."

A/N: By the way, my head canon for the 'ancient songs' the Face of Boe sings in his head is Sexy and I Know It. I'll just leave that here.