WARNING: this fic is not ideal for Rose fans
Disclaimer: if I owned these characters I wouldn't have to keep offering TenII and Donna comfort all the time!
A/N: written for the hc_bingo challenge prompt "major illness or injury"

One Stop Swap
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It was as the metacrisis version of the Doctor stepped over the threshold of a large room that he knew exactly what this was. It was a trap. So much for being told he was finally being allowed to leave his cell and breathe some decent air for a change.

All around the wall was a series of mirrors all wired together as though they formed a solar panelled bomb. His heart sunk at the sight. "Did you dismantle another TARDIS?" he pithily asked.

"It's the same one," his companion confirmed his worse fears.

There was a sudden appalling mechanical hum that burst into his head before attacking his throat and choking the life out of his body. It burned and consumed him from the pit of his stomach.

He stood glaring at Rose as the force within him caused his arms to reach out in surrender; the glow rampantly overwhelming his body as the fire burned bright.

"What have you done to me?!" he cried in horror, powerless to do anything but let the energy swirl around him in small eddies.

Rose merely stood triumphant before his wilting body, without guilt or recrimination. "I'm replacing you," she informed him. "You'd forgotten about the dimension cannon, but I hadn't. I got it recommissioned, and now it's finally working. If I'm right, you'll soon disappear and the Doctor will replace you, putting him where he should be."

"And where exactly is that, Rose Tyler?" he demanded to know, gritting his teeth against the pain that threatened to tear him apart at any second. If he was going to die, he was going to have the truth before he went.

"Next to me," she replied. "It should have been me by his side, and not that ginger…" Her words got lost in the sneer on her face as she thought about Donna Noble.

"You hate her," he realised in a gasp. "All you cared about was her delivering your message."

"All she did was get me lumbered with you," Rose spat out. "If it wasn't for her I would have been allowed to stay in the real universe!"

"She was innocent," he argued. "Be reasonable."

"Be reasonable, he says," she mocked him. "Well, seeing as you're so taken with her, you won't mind being dumped with her instead. And I'll get back MY Doctor."

"Rose….," he began to say, but he faded away from sight, causing her to shriek with excitement.

"Here he comes!" she declared as something else began to take his place.

But when it materialised, it wasn't him. Instead it was a large cardboard box.

"Doctor?" she pathetically wailed. "Doctor!"

~0~0~

The burning was replaced with cold. So cold. He could feel his teeth chattering as he fought to retain any heat left in his body within the oozing blackness.

Then just as suddenly as he had been snatched away, he was reassembled. Every atom carefully but quickly manipulated, so that as he was aware of having a solid body again, the burning petered out to leave him renewed and blinking into the light of an unfamiliar room.

"There he is, and about time too," a female voice from behind him fondly announced. A very familiar voice.

"Donna?" he squeaked in query, twirling on the spot to try and see where she was.

"Whoa, Spaceman! Not so fast," she cautioned him, holding up a hand to partially cover her face. "I see you didn't get the dress code memo again. Don't you ever wear clothing?"

"Clothing?" he pondered, looking down at himself.

"You're naked!"

"Oh!" He quickly covered his lower torso with his hands, now also aware of an unwelcome breeze around his vitals. "It wasn't intentional."

"I know," she allowed, and edged closer to peer at his face. "Now that isn't fair! I was expecting you to look years older."

He grinned. Last time he'd seen his face he had aged by at least a decade. Did this mean he had regenerated? There was a more pressing question to get answered first.

"How did I get here?"

She tilted her head and smirked. "Once upon a time a mummy and a daddy loved each other very much…"

"Not that sort of 'how did I get here'," he grouched. "I mean, how did I change dimensions?"

"Oh that one," she pretended to realise. "Well, some idiot… Oops! I mean, someone started up the dimension cannon despite being warned not to; again. So I harnessed the back energy through the Rift, reversed the polarity using that button there, Bob's your uncle, Fanny's your aunt, and here you are. Da dah!" After a few seconds, as he gawped at her, she commented, "You could at least sound pleased."

Finding his strained voice, he asked, "What would have happened if you hadn't snatched me at the right moment?"

She turned and sniffed, just like the Doctor would have done, and toyed with a switch on the workstation before her. "You would have died. Your particles would have been scattered across that universe."

"So the dimension cannon wasn't working properly," he reasoned out.

"Not without me it couldn't," she supplied. "Thankfully I knew how to look for your time signature, so I didn't have a great deal of trouble latching onto you once I persuaded Torchwood to let me near the Rift."

He nodded. Of course she could trace him; they shared some DNA after all. Here came the sixty-four thousand dollar question. "Why did you look for me?"

"Well…," she blustered. "You know. I suddenly had all this knowledge again, thanks to the Master chasing me. I'll tell you all about that later. Then I won the lottery, so I had all this money and spare time; pots of money. Millions, in fact."

"Must have been terrible," he pretended to sympathise.

"Yeah," she agreed. "And once you've set up a few charitable trusts, what's there left to do? So I thought I'd design and fund some technology then come and get you from the alternate world."

"That was nice of you."

"I thought so. Left Rose a nice little present when I nabbed you. I hope she likes Barbie dolls." She beamed a smile at him. "Is it good to be back? I had a bedroom specially decorated for you and everything."

"Well, it's certainly a surprise," he admitted, blowing out a breath. "I thought I was dead."

"Technically you were," she stated. "It was that small energy burst that pinpointed your location."

"But there was a blaze of light," he argued.

"That was me," she sheepishly confessed. "I had to make sure I definitely got you, so I ramped things up a bit."

"Seems right." He then considered, "That explains the level of pain. I hadn't expected to regenerate. I did regenerate, didn't I?"

"Yes. That was also me. A little gift via the Master, shall we say." She bobbed her head up and down. "And your dad," she added.

"Dad?!" he spluttered. "Since when have I had a dad?"

"Look, I know you had a sort of virgin birth, but we have to live in the real world now, where people are expected to have dads. Because," she offered, walking over to her handbag and opening it up, "and I know this might come as a huge surprise for you, but physically you are old enough to be my son." She pulled out a compact mirror and held it out towards him. "Do you want a look? It's not bad at all."

Trembling, he took it. "The Master kick started things, you say?"

"The Doctor put in place a defence mechanism to stop anyone exploiting me when he wiped my memory of him, you, and everything," she explained. "But what he didn't allow for was the weird power the Master had acquired himself. A bit like Voldemort, when you think about it."

"Are you alright now?" he worried.

"Right as ninepence," she cheerily assured him. "Now look in the bloody mirror and stop delaying the inevitable."

Waiting for her nod of encouragement, he drew in a breath, and then held the mirror up. The face gazing back at him wasn't particularly strange in its components. He turned his head this way and that to get a better view.

"I look like you. Well, sort of," he eventually proclaimed. "And young! How old would you say? Seventeen, eighteen, nineteen?" he queried.

"There's still some Doctor in there, with ginger highlights. You choose a number," she said. "Which age do you fancy being? Although it suits me better if you don't make me an ex-teen mum."

"How old are you now?" he suddenly asked.

"Pushing forty; and that's all you're getting, Sunshine!" she huffed. "That's a question you should never ask."

"Cool the beans, Mum!" he teased. "Hang on, that is weird, calling you that." His bottom lip then quivered and tears welled up in his eyes. "I've got a mum, a real mum."

"And I've finally got a real boy," she whimpered, throwing her arms around his thin shoulders. "Oh gawd, you've set me off now," she complained, wiping desperately at her eyes before returning to cuddle him close.

"What about the Doctor? Have I got a dad I can see?" he wondered from next to her neck.

"He erm…" She anxiously licked her lips. "That version of him is dead. The new him doesn't look old enough to wipe his nose let alone be your dad. Sorry."

He accepted that. "I thought as much. He feels different in my mind. Perhaps next time he dies he will come for me?"

"Perhaps," she reluctantly agreed. "He came and peeped at me once, but otherwise he stays well away, with his new companions. At least you've still got a Gramps. I'll tell you what else you've got: a cold bum. Let's go and find you some clothing. I'm sure Jack will oblige."

"Mum!"

"What?! I only mentioned his name," she defended herself. "He was very friendly when I turned up here in the Hub."

"Don't. Just don't," her new son warned.

"Blimey! Talk about just like your father," she grouched as they walked away.

A/N2: I used one of the other hc_bingo prompts to write a sequel; thanks to something helloprilly said when she read this through for me.

The sequel is called "Two Seconds Late".