Doo doo doo dooo doo doooooooo dooooooo...
The Doctor and The Master as The Odd Couple, with a couple of deliberately pilfered lines.
"Doctor, what's this sticky stuff all over my screwdriver?"
"Oh, didn't I tell you? The toilet's blocked again. I thought that if I reversed the polarity of the-"
"But you can't use my screwdriver, isomorphic controls, remember?"
"Well, yes, I know that, but I needed something to loosen the-"
"No! No! Don't you dare finish that sentence."
"-debris, and it was the only thing lying about at the time."
"That's it, I'm taping over your copy of Britain's Got Talent."
"Fine by me. I'm not the one with the crush on Ant. Or is it Dec?"
"And I get to blow up the next planet we go by, using my brand new doomsday device."
"Sorry, can't do that, I'm using it to prop up the table in the fourth room over."
"Don't point that finger at me unless you intend to use it."
The Master sat back and twirled in his chair, staring up at the ceiling of the TARDIS. "Funny, I haven't thought of killing in weeks."
The Doctor gently prised apart some of the nearest console and quickly glanced up. "I fail to see the humour."
"It's the drumming, the constant drumming, Doctor. It usually compels me toward fresh blood every three days or so. But lately the bloodlust has diminished, leaving only a slight yearning for delivering long and overly dramatic speeches."
"Oh, that's the suppressant I put in your lemon and lime yoghurt every morning."
"I did it for your own good, and you just said it was beneficial."
"Doctor!" The Master sprung from his chair, his coat billowing behind him. "I knew you weren't above mind control. You're learning from the best."
The Doctor nodded vigorously, adjusting his spectacles. "Yes, yes, that's quite possible. Master?"
The Master stretched, cat-like. "I like it when you use my name."
"It's why I make sure to so at least once every day," The Doctor confirmed. He returned to his questioning tone. "You wouldn't mind putting your finger just here and holding this in place?.."
"I need to fit the flux capacitor."
The Master frowned, scrunching up his face in exaggerated contortion. "The TARDIS doesn't need a flux capacitor."
"No, strictly speaking, it doesn't. But it's what I've decided to call this spacey-wacey thing."
"What spacey-wacey thing?"
"This one, right here," The Doctor said, pointing.
"Why does that look like a section of The Valiant?"
"Because it is."
"You cannibalised my ship for yours?"
The Doctor rocked back on his converses. "It's not like you haven't done the same."
"No, but I'm evil."
"And you're not."
The Master whirled around, letting go at the precise moment The Doctor attempted to attach his spacey-wacey flux capacitor. "I'm making myself a daiquiri with the last banana, and there's nothing you can do to stop me."
"Oh, that's all right, I already ate all your jelly babies. We're about even."
"One day I will have my revenge!"
"Okay, but please don't make it Thursday, I've got a hair appointment..."