'Hell, yes,' said Vimes. 'The muggers. He got this- he got his scar that way. A good old Ankh-Morpork welcome. But he was a tough man. Took 'em both down, no problem.'
'This time, there were three,' said Sweeper. 'Well, three's trickier, of course, but-'
'You're the policeman. You guess the name of the third man, Mister Vimes.' Vimes hardly had to think. The answer erupted from the depths of darkest suspicion. 'Carcer?'
'He soon settled in, yes.'
'The bastard was in the next cell! He even told me he'd grabbed some money.'
'And you're both stuck here, Mister Vimes. This isn't your past, any more. Not exactly. It's a past. And up there is a future. It might be your future. But it might not be. You want to go home now, leaving Carcer here and the real John Keel dead? But there'll be no home to go to, if you could do that. Because young Sam Vimes wouldn't get a swift course in basic policing from a decent man if you did. He'll learn it from people like Sergeant Knock and Corporal Quirke and Lance-Corporal Colon. And that might not be the worst of it, by a long way.' Vimes shut his eyes. He remembered how wet behind the ears he'd been. And Fred . . . well, Fred Colon hadn't been too bad, under the half-hearted timorousness and lack of imagination, but Quirke had been an evil little sod in his way and as for Knock, well. Knock had been Fred's teacher and the pupil wasn't a patch on the master. What had Sam Vimes learned from Keel? To stay alert, to think for himself, to keep a place in his head
free from the Quirkes and Knocks of the world, and not to hesitate about fighting dirty today if that was what it took to fight again tomorrow. He'd often thought he'd have been dead long ago if it wasn't for- He looked up sharply at the monk. 'Can't tell you that, Mister Vim.es,' said Lu-Tze. 'Nothing's certain, 'cos of quantum.'
'But, look, I know my future happened, because I was there!'
'No. What we've got here, friend, is quantum interference. Mean anything? No. Well... let me put it this way. There's one past, and one future. But there are two presents. One where you and your evil friend turned up, and one where you didn't. We can keep these two presents going side by side for a few days. It takes a lot of run time, but we can do it. And then they'll snap back together. The future that happens depends on you. We want the future where Vimes is a good copper. Not the other one.'
'But it must've happened!' snapped Vimes. 'I told you, I can remember it! I was there yesterday!'
'Nice try, but that doesn't mean anything any more,' said the monk. Trust me. Yes, it's happened to you, but even though it has, it might not, 'cos of quantum. Right now, there isn't a Commander Vimes-shaped hole in the future to drop you into. It's officially Uncertain. But might not be, if you do it right. You owe it to yourself, commander. Right now, out there, Sam Vimes is learning to be a very bad copper indeed. And he learns fast.' The little monk stood up. 'I'll let you think about that,' he said. Vimes nodded, staring at the gravel garden. Sweeper crept away quietly and went back into the temple. He walked to the other side of the office. He removed a strange-shaped key from around his neck and inserted it into a small door. The door opened. Brilliant sunlight burst ahead of him. He walked on, his sandals leaving the cold flagstones and walking on to well-trodden earth in broad, hot daylight. The river had a different course this far back in the past, and present- day residents of Ankh-Morpork would have been surprised at how pleasant it looked, seven hundred thousand years ago. Hippos sunbathed on a sandbank out in mid-stream and, according to Qu, were getting troublesome lately - he'd had to set up a little temporal fence around the camp at nights, so that any hippo trying to wander in among the tents found themselves back in the water with a headache. Qu himself, his straw hat protecting his head from the hot sun, was supervising his assistants in a vined-off area. Lu-Tze sighed as he walked towards it. There were going to be explosions, he knew it. It wasn't that he disliked Qu, the order's Master of Devices. The man was a sort of engineering equivalent of the Abbot. The Abbot had taken thousand-year-old ideas and put them through his mind in a new way, and
as a result the multiverse had opened for him like a flower. Qu, on the other hand, had taken the ancient technology of the Procrastinators, that could save and restore time, and had harnessed it to practical, everyday purposes, such as, yes, blowing people's heads off. It was something that Lu-Tze tried to avoid. There were better things to do with people's heads. As Lu-Tze approached, a line of joyful, dancing monks wove their way along a bamboo replica of a street, letting off firecrackers and banging gongs. As they reached a corner the last monk turned and lightly tossed a little drum into the outstretched arms of a straw dummy. The air shimmered, and the figure disappeared with a small thunderclap. 'Nice to see something not blowing anyone's head off,' said Lu-Tze, leaning on the vine rope. 'Oh, hello, Sweeper,' said Qu. 'Yes. I wonder what went wrong. You see, the body should have moved forward by a microsecond and left the head where it was.' He picked up a megaphone. Thank you, everyone! Places for another run! Soto, take over, please!' He turned to Lu-Tze. 'Well?'
'He's thinking about it,' said Sweeper. 'Oh, for heavens' sake, Lu-Tze! This is completely unauthorized, you know! We're supposed to prune out rogue history loops, not expend vast amounts of time keeping them going!'
'This one's important. We owe it to the man. It wasn't his fault we had the major temporal shattering just as he fell through the dome.'
'Two timelines running side by side,' moaned Qu. That's quite unacceptable, you know. I'm having to use techniques that are completely untried.'
'Yes, but it's only a few days.'
'What about Vimes? Is he strong enough? He's got no training for this!'
'He defaults to being a copper. A copper's a copper, wherever he is.'
'I really don't know why I listen to you, Lu-Tze, I really don't,' said Qu. He glanced at the arena and hurriedly raised his megaphone to his lips. 'Don't hold it that way up! I said don't hold-' There was a thunderclap. Lu-Tze didn't bother to look round. Qu lifted the megaphone again and said, wearily, 'All right, someone please go and fetch Brother Kai, will you? Start looking around, oh, two centuries ago. You don't even use these very useful devices I, er, devise,' he added to Lu-Tze. 'Don't need to,' said Lu-Tze. 'Got a brain. Anyway, I use the temporal toilet, don't I?'
'A privy which discharges ten million years into the past was not a good idea, Sweeper. I'm sorry I let you persuade me.'
'It's saving us fourpence a week to Harry King's bucket boys, Qu, and that's not to be sneezed at. Is it not written: “a penny saved is a penny earned”? Besides, it all lands in a volcano anyway. Perfectly hygienic.' There was another explosion. Qu turned and raised his megaphone. 'Do not bang the tambourine more than twice!' he bellowed. 'It's tap-tap-throw- duck! Please pay attention!' He turned back to Sweeper. 'Four more days at most, Lu-Tze,' he said. 'I'm sorry, but after that I can't hide it in the paperwork. And I'll be amazed if your man can stand it. It'll affect his mind sooner or later, however tough you think he is. He's not in his right time.'
'We're learning a lot, though,' Lu-Tze insisted. For a perfectly logical chain of reasons Vimes ended up back in time even looking rather like Keel! Eyepatch and scar! Is that Narrative Causality or Historical Imperative or just plain weird? Are we back to the old theory of the self-correcting history? Is there no such thing as an accident, as the Abbot says? Is every accident just a higher-order design? I'd love to find out!'
'Four days,' Qu insisted. 'Any longer than that and this little exercise will show up and the Abbot will be very, very annoyed with us.'
'Right you are, Qu,' said Sweeper meekly. He'll be annoyed if he has to find out, certainly, he thought as he walked back to the door in the air. He'd been very specific. The Abbot of the History Monks (the Men In Saffron, No Such Monastery . . . they had many names) couldn't allow this sort of thing, and he'd taken pains to forbid Lu-Tze from this course of action. He had added, 'but when you do, I expect Historical Imperative will win.' Sweeper went back to the garden and found Vimes still staring at the empty baked-bean tin of Universal Oneness. 'Well, commander?' he said. 'Are you really like . . . policemen, for time?' said Vimes. 'Well, in a way,' said Sweeper. 'So . . . you make sure the good stuff happens?'
'No, not the good stuff. The right stuff,' said Sweeper. 'But frankly, these days, we have our work cut out making sure anything happens. We used to think time was like a river, you could row up and down and come back to the same place. Then we found it acted like a sea, so you could go from side to side as well. Then it turned out to be like a ball of water; you could go up and down too. Currently we think it's like . . . oh, lots of spaces, all rolled up. And then there are time jumps and time slips and humans mess it up too, wasting it and gaining it. And then there's quantum, of course.' The monk sighed. There's always bloody quantum. So what with one thing and another, we think we're doing well if yesterday happens before tomorrow, quite frankly. You, Mister Vimes, got
caught up in a bit of ... an event. We can't put it right, not properly. You can.' Vimes sat back. 'I've got no choice, have I?' he said. 'As my old sergeant used to say . . . you do the job that's in front of you.' He hesitated. 'And that's going to be me, isn't it? I taught me all I know . . .'
'No. I explained.'
'I didn't understand it. But perhaps I don't have to.' Sweeper sat down. 'Good. And now, Mister Vimes, I'll take you back inside and I'll give you some background on the sergeant and we'll work out what you need to know from all this, and we can set up a little loop so that you can tell yourself what you need to know. No addresses, though!'
'And what'll happen to me?' said Vimes. 'The me sitting here now? The . . . er ... other me walks away and me, this me, you understand . . . Well, what happens?' Sweeper gave him a long, thoughtful look. 'Y'know,' he said, 'it's very hard to talk quantum using a language originally designed to tell other monkeys where the ripe fruit is. Afterwards? Well, there will be a you. As much you as you are now, so who can say it's not you? This meeting will be ... a sort of loop in time. In one sense, it will never end. In a way, it'll be-'
'Like a dream,' said Vimes wearily. Sweeper brightened. 'Very good! Yes! Not true, but a very, very good lie!'
'You know, you could've just told me everything,' said Vimes. 'No. I wouldn't be able to tell you everything and you, Mister Vimes, aren't in the mood for games like that. This way, a man you trust - that's you - will tell you all the truth you need to know. Then we'll do a little of what the younger acolytes call “slicing and glueing”, and Mister Vimes will go back to Treacle Mine Lane a little wiser.'
'How are you going to get hi- me back to the Watch House? Don't even think about giving me some kind of potion.'
'No. We'll blindfold you, twirl you round, take you the long way, and walk you back. I promise.'
'Any other advice?' said Vimes gloomily. 'Just be yourself,' said Sweeper. 'See it through. There'll come a time when you'll look back and see how it all made sense.'
'Really?'
'I wouldn't lie. It'll be a perfect moment. Believe me.'
'But. . .' Vimes hesitated.
'Yes?'
'You must know there's another little problem if I'm going to be Sergeant Keel. I've remembered what day this is. And I know what's going to happen.'
'Yes,' said Sweeper. 'I know, too. Shall we talk about that?' Captain Tilden blinked. 'What happened there?' he said. 'Where?' said Vimes, trying to fight down nausea. Time coming back had left him with a horrible sensation that he was really two people and neither of them was feeling at all well. 'You blurred, man.'
