This was beginning to seem very familiar, standing on the bridge of the Valiant facing down the Master. There were a couple of minor differences; first of all he was with Rose rather than Martha and Jack, and second of all instead of menacing him with a laser screwdriver the Master was bent double laughing his head off.

"Hang on," said the Doctor, "Weren't you dead?"

At that the Master slapped his thighs and managed to wheeze out, "Oh stop it, you're killing me."

Eventually the Master recovered from his hysterical fit long enough to order the Doctor and Rose locked away in a cell.

Not a person to cast blame Rose glared at the Doctor and said, "This is all your fault."

"My fault? Just because I didn't foresee the Master using his funeral pyre and a bit of tacky jewellery to sneak through the cracks between the universes and try to takeover this version of Earth, this is suddenly all my fault."

"No, Doctor. It's your fault because I must have mentioned my new boss, Harold Saxon, twenty or thirty times and it never occurred to you to mention that it was the name used by an evil Time Lord who tried to conquer the other universe."

"Ah. When you put it that way I can see how it does look like it's a little bit my fault."

The Master demanded that the Doctor be brought to him. He was sitting with his feet on the table wearing a black suit with a white shirt.

He's quite tasty, thought the little internal Donna Noble that had taken over a seldom used corner of the Doctor's mind.

Stop that, he thought back.

Yeah, that wasn't me, replied internal Donna.

"I'm sorry," said the Master. "Am I interrupting you and your imaginary friend?"

"What do you want, Master."

"You're a human," he said gleefully.

"Half human, half Time Lord," corrected the Doctor.

"Half Time Lord?" the Master sounded unconvinced.

"Er, okay, more like an eighth Time Lord."

The Master giggled, actually giggled. Git. If the Master had gotten himself trapped in a human body the Doctor wouldn't have giggled. Okay, he probably would giggle, but he'd at least have the decency to do it behind the Master's back.

It was insulting was what it was. The Master hadn't bothered to age the Doctor up to a hundred, chain him in a kennel or even keep him locked in his cell twenty four hours a day. It was as though now he was human he wasn't a threat.

"Do I still call you Doctor?" The Master asked, "Or have you taken on some silly human name, John Smith, or the like?"

Rose had suggested early on that he take a human name. He'd considered it, even going as far as to make a few suggestions; he'd gotten as far as Hamish McTimelord before she had a change of heart and decided he should carry on calling himself the Doctor.

"No, it's still Doctor."

What was even more insulting was that the Master did keep Rose locked up. As though just because she was a highly trained Torchwood agent with an affinity for large and scary weapons she was more dangerous than the Doctor.

"Don't you think we should be trying to escape?" she demanded when the Doctor strolled back into their cell with his hands deep in his pockets.

"I'm working on it."

Plan A (which involved the laser screwdriver, the Valiant's engines and a small black hole) was going quite well until the Master distracted him by saying. "Humans age terribly quickly, don't they. Look, you've got a grey hair."

To his credit the Doctor managed to contain himself for several seconds before dashing over to the nearest reflective surface.

After Plan B went tits up the Master decided this couldn't go in. Being rather reluctant to actually kill the Doctor, especially now that he wouldn't regenerate, the Master resorted to the time honoured method of blackmail.

"Look, if you stop trying to ruin my plans then I'll build you a new Time Lord body."

"I don't want a new body."

"Of course you do."

"I don't want a new body from you."

"Fine then, cut off your nose to spite your face,"

"Why do you want to rule the Earth?"

The Master shrugged, "It's something to do, isn't it."

"It's not just another elaborate scheme to get my attention, is it?"

"As if I'd want the attention of a mere human."

"Master, have you ever heard the saying about the lady and protesting too much?"

The thing is that after the Master had conquered the Earth and had all those giant statues of himself carved he really wasn't sure what else to do. He settled for hanging around the Valiant chatting up the Doctor.

"We could go travelling."

"Sure. Paris is lovely this time of year."

"No, really we could. The Last of the Time Lords and his human pet. You could wear a shiny cat-suit and scream a lot."

Personally the Doctor thought that revealed rather more about the Master's fantasies than he really wanted to know. "No thanks, I've got other plans."

The Doctor's other plans became clear one day when he was mooching around the Valiant's engine decks and stumbled across a plinth.

"Oh, Master," he sighed, "never change."

Rose was rather surprised when an ancient looking column sat atop a plinth materialised behind her. Even more surprised when it cracked open and the Doctor stepped out.

"Shall we go?"

"Oh, yes."

"Just one thing before we go..."

The Master, the Doctor and Rose stood in the console room of what had until recently been the Master's TARDIS.

"No," said Rose.

"No," said the Master.

"No," thought Internal Donna.

The Doctor turned his best puppy dog eyes on Rose; it was a look he knew she couldn't resist.

"Oh, all right," she conceded. "But you're the one who has to feed him and walk him."