Thud!

inwardly. Good old Cheery. She knew what a Vimes BLT was all about. It was about having to lift up quite a lot of crispy bacon before you found the miserable skulking vegetables. You might never notice them at all.
    “I want you to take Angua down there with you again,” he said. “And…yes, Lance Constable von Humpeding. Our little Sally. Just the job for a vampire who fortuitously has arrived in the nick of time, eh? Let’s see how good she is.”
    “Just those two, sir?”
    “Er, yes. They both have very good night vision, yes?” Vimes looked down at his sandwich, and mumbled: “We can’t take any artificial light down there.”
    “A murder investigation in the dark , sir?”
    “I had no choice!” said Vimes hotly. “I know a sticking point when I see one, Captain. No artificial light. Well, if they want to play silly buggers, I’m their boy. You know about mines, and both the ladies have got night vision built in. Well, the vampire has, and Angua can practically see with her nose. So that’s it. Do the best you can. The place is full of those damn glow beetles. They should help.”
    “They’ve got vurms?” said Carrot. “Oh. Well, I know some tricks there, sir.”
    “Good. They say a big troll did it and ran away. Make of that what you will.”
    “There might be some protests about Sally, sir,” said Carrot.
    “Why? Will they spot she’s a vampire?”
    “No, sir, I don’t think they—”
    “Then don’t tell ’em,” said Vimes. “You’re the…smelter, it’s up to you what, er, tools you use. Seen this?”
    He waved the report about the three officers he was trying not to think of as deserters.
    “Yes, sir. I was meaning to talk to you about that. It might help if we changed the patrols a bit,” said Carrot.
    “How do you mean?”
    “Er…it would be quite easy to arrange the patrol schedules so that trolls and dwarfs don’t have to go on the beat together, sir. Um…some of the lads say they’d be a bit happier if we could…”
    Carrot let the sentence die away in the stony glare.
    “We’ve never paid any attention to an officer’s species when we do the roster, Captain,” said Vimes coldly. “Except for the gnomes, of course.”
    “There’s your precedent, then—” Carrot began.
    “Don’t be daft. A typical gnome room is about twice the size of a shoebox, Captain! Look, you can see this idea is nuts. Dangerous nuts, too. We’d have to patrol troll with troll, dwarf, with dwarf and human with human—”
    “Not necessarily, sir. Humans could patrol with either of the others.”
    Vimes rocked his chair forward. “No, they couldn’t! This is not about common sense, this is about fear! If a troll sees a dwarf and a human patrolling together, he’ll think: ‘There’s the enemy, two against one.’ Can’t you see where this is going? When a copper’s in a tight corner and blows his whistle for backup, I don’t want him demanding that when it arrives it’s the right damn shape!” He calmed down a little, opened his notebook, and tossed it on the desk. “And talking of shapes, do you know what this means? I spotted it in the mine, and a dwarf called Helmclever scrawled it with some spilt coffee, and you know what? I think he was only half-aware that he’d done it.”
    Carrot picked up the notebook and regarded the sketch solemnly for a moment.
    “Mine sign, sir,” he said. “It means ‘The Following Dark.’ ”
    “And what does that mean?”
    “Er…that things are pretty bad down there, sir,” said Carrot earnestly. “Oh dear.” He put the notebook down slowly, as if half-afraid that it might explode.
    “Well, there has been a murder, Captain,” Vimes pointed out.
    “Yes, sir. But this might mean something worse, sir. Mine sign is a very strange phenomenon.”
    “There was a sign like it over the door, only there was just one line and it was horizontal,” Vimes added.
    “Oh, that’d be the Long Dark rune, sir,” said Carrot dismissively. “It’s just the symbol for a mine. Nothing to worry about.”
    “But this other one is? Is it anything to do with grags sitting in a room surrounded by lighted candles?”
    It was always nice to surprise Carrot, and this time he looked amazed. “How did you work that out, sir?”
    “It’s only words, Captain,” said Vimes, waving a hand. “ ‘The Following Dark’ doesn’t sound good. Time to stay brightly lit, maybe? When I met them, they were surrounded by candles. I thought maybe it was