"Excuse me, Smithy," said Laura, knocking at the doorjamb of the sergeants' office. "I mean - sorry - sarge."

"Wot is it?"

"Have you heard of this United Nations Intelligence Taskforce? Only we've got a live one in custody - claims to be their scientific advisor. Sergeant Ackland said you might know something about it."

Laura showed Smiffy the pass the man had given her. He opened it and gave it a cursory glance.

"Yeah, I know UNIT. Got a mate who's a UNIT corporal as it goes. Let me have a word."

"Righto."

They walked back out to custody, Smiffy flicking the UNIT pass against his hand.

"He's over there in the Austin Powers get-up."

"Cheers, Laura. Excuse me, sir."

The man in question was indeed attired in a velvet smoking jacket and frilly white shirt, with tall, black, dramatic leather boots reaching to his knees. He was seated on the custody bench between Reg and a female companion.

"Well, it's about time!" the companion exclaimed in girlish indignation upon Smiffy's arrival.

The man stood up to speak with him. "I do hope we can clear up this misunderstanding, sergeant, er—"

"Sergeant Smith. Where'd you get this?"

"UNIT headquarters," the man replied. "I believe that's generally where they issue them."

"And you are?"

"Doctor John Smith. Though I'm usually known simply as the Doctor. Can you read, sergeant?"

The man loomed a few inches taller than Smiffy. He had a big presence in the room with his sensual, theatrical clothes and white, woolly hair. His eyes were wise, and warm, and piercing, and at the moment imbued with arrogant purpose.

But Smiffy was not one to be intimidated. "Look, I don't know what your game is, mate. But this pass expired before most of my relief was a twinkle in their old man's proverbial. So it won't do you no favours round here."

"I see. Well, sergeant, allow me to do a favour for you. By informing you that you, sir, are even more of a closed-minded buffoon than the soldier who issued me that pass—"

"What the Doctor means to say, " interjected the female, "is that he has a long-standing association with UNIT, and he's certain if you phone them up they'll vouch for his credentials. And mine too, for that matter."

"And what's your name?"

"Josephine Grant," she said, importantly. Then she flashed her most winning smile. "Or Jo, if you like."

She was small, but sparky. Like her tall companion, she too had presence, with her big shiny eyes and short (short!) miniskirt and fluffy faux-fur coat, and her own pair of tall, black boots.

Smiffy habitually gave her the once over, but he wasn't convinced. "Don't worry, I'll be phoning UNIT awright. We're well acquainted. And in all my time I've never seen a UNIT soldier dressed like you two."

"Oh, we're not soldiers," said Jo. "We're scientists. Well, the Doctor is, and I'm his assistant. And when your officers arrested us we were in the middle of an important investigation."

Smiffy ignored her and turned to Laura. "What are they charged with?"

"We arrested him for arson and criminal damage at the old warehouse on Harrow Road. There had obviously been an explosion of some sort among some fancy electrical equipment. He showed us where it happened."

"That don't mean he started it."

"No, but he kept telling us none of this was down to her and he's sorry he dragged her into it. Sounded a bit suspicious, and he couldn't account for his presence in the warehouse, despite admitting to damaging the equipment with a screwdriver. So we arrested him. She insisted on coming along to keep him company."

The Doctor was growing impatient. "Now look, sergeant, I assure you that this a complete waste of everybody's time. Can't you listen to reason, man?"

"That's right," said Jo. "The Doctor didn't start that fire - he stopped the whole room from going up in smoke! You should be thanking him not locking him up. You've arrested the wrong man!"

"Yes, well never mind that, Jo. This is far more serious than wrongful arrest. Sergeant Smith, as I've been trying to explain to your officers, your detaining me could seriously endanger us all. One of the most devious criminal minds the Earth has seen for - well, for thirty odd years - is masterminding a dangerous plot from the back room of that warehouse. It's only by sheer luck that we stumbled across his base of operations, and I was able to dismantle some of his equipment, and as Jo says, stop the place from going up in smoke. But the man himself was absent, and I should think it would be the priority of the local authorities - by which I mean you - to find him and lock him out of harm's way as soon as humanly possible. Or preferably, sooner."

"Okay," said Smiffy shortly. "Who is this geezer then?"

"Well," The Doctor rubbed his neck. "I don't know his name."

"That's convenient."

"What I mean is, I don't know the name he'd be using. He goes by many names. But I can guarantee you that whatever it is, it'll be some form of the word 'master'."

"Well what's he look like, this master?"

The Doctor rubbed his neck some more. "I can't tell you that either."

"I suppose he goes by many faces."

"Yes. Yes he does as a matter of fact."

Smiffy sighed.

"Well what's he sposed to have done then?"

"Now that I do know. He's put in place a temporal recursion loop that operates on a local spatial scale of approximately three miles radius from the core generator in that warehouse."

"What's that when it's at home?"

"It's a powerful force that dooms anyone trapped within its influence to an eternity of ethological circularity."

"Circuwhat?"

"Put simply, sergeant, repeating yourself. Doing the same things over and over again."

"So what you're telling me is, this bloke's guilty of boring us to death."

The Doctor's mouth twitched in the shadow of a smile. "Yes. I suppose that's exactly what I'm saying."

"You're right," said Smiffy. "He is evil."

He cast a glance at June behind the custody desk, who shared a sympathetic smile.

"But you've sorted him out now?" piped up Reg from the sidelines, with more sincerity than Smiffy was comfortable with.

"I simply reversed the polarity of the neutron flow," explained the Doctor. "But the damage that did won't hold the Master up for long. And the only reason he hasn't boosted his recursion loop to engulf the whole of London - or possibly the world - is that his energy source overheated, causing the warehouse explosion. But once that's repaired…"

"You've just got to let us go!" pleaded Jo. "The Doctor's the only one who knows how to stop the Master!"

Reg nodded, pursing his lips, his grey eyes thoughtful.

"So, sergeant," said the Doctor with an optimistic lisp. "Will you help us find the Master and put an end to his operation before it's too late?"

"Fraid not."

"May I ask why?"

"You may," said Smiffy. "It's because you are, at the risk of sounding a bit Shakespearean, what we in the Met commonly refer to as an utter nutter."

"Now, look here—" the Doctor started angrily.

"Yes, hold on!" exclaimed Jo.

"Lock him up, June. Laura, it's arson, pass the case on to CID. Reg?"

Reg took the Doctor by the arm. "Come along, sir."

"And you," Smiffy said to Jo, "you can come wiv me. I know someone who'll want to hear your story."

"I'm not leaving the Doctor!"

The Doctor turned back to Jo. "It's all right, Jo. I'm sure we can get this sorted soon enough. Just do as they say."

He smiled kindly at her, and she smiled back with complete faith and resignation. "If you say so, Doctor."

"I do."

"Sir, if you wouldn't mind," repeated Reg, and nudged the Doctor towards the custody desk.

Jo shrugged to Smiffy.

"All right then, sergeant," she said. "Drag me away to be sacrificed or tied up or married off or mind probed, or whatever it is you want to do with me."

"With any luck," muttered Smiffy, leading her through the internal doors of the station, "in ten minutes that won't be my problem any more."