"In retrospect, Phoenix should have been a signal that something really weird was happening," Mike continued. "It took us a long time to dig our way into the rubble and what we found was disturbing. Bomb shelters, cold stores, closed-circuit air-conditioning… and fifty kilograms of pharmaceutical-grade cocaine in a vault. Plus an arsenal like a National Guard depot. But there were no bodies…" He trailed off introspectively. Too tired for this, he thought dizzily.

"Okay, now fast-forward. You've had a series of tip-offs from source Greensleeves, leading up to Greensleeves turning himself in three days ago," Colonel Smith stated. "What about the saliva sample? It's definitely him?"

Mike shrugged. "PCR says so. Matthias is definitely source Greensleeves. He got us an armored fortress in downtown Cambridge with fifty kilos of pharmaceutical-grade cocaine and a Twilight Zone episode to explain, plus a series of crack warehouses and meth labs up and down the coast. Biggest serial bust in maybe a decade. He's-" Mike shook his head. "I've spent a couple of hours talking to him and it's funny, he doesn't sound crazy, and after watching that video-well. Matt-Greensleeves-doesn't sound sane at first, he sounds like a nut. Except that he's right about everything I checked. And the guy vanishing in front of the camera is just icing on the cake. He predicted it." Mike shook his head again. "Like I said, he sounds crazy-but I'm beginning to believe him."

"Right." Colonel Smith broke in just as a buzzer sounded, and a marine guard opened the outer door for a steward, who wheeled in a trolley laden with coffee cups and flasks. "We'll pause right here for a moment," Smith said. "No shop talk until after coffee. Then you and Pete can tell us the rest."

The debriefing room wasn't a cell. It resembled nothing so much as someone's living room, tricked out in cheap sofas, a couple of recliners, a coffee table, and a sideboard stocked with soft drinks. The holding suite where they'd stashed Greensleeves for the duration didn't look much like a jail cell, either. It had all the facilities of a rather boring hotel room-beds, desk, compact en-suite bathroom-if the federal government had been in the business of providing motel accommodation for peripatetic bureaucrats.

But the complex had two things in common with every jail ever built. First, the door to the outside world was locked on the outside. And second, the windows didn't open. In fact, if you looked at them for long enough you'd realize that they weren't really windows at all. Both the debriefing room and the holding suite were buried in a second-story basement, and to get in you'd have to either prove your identity and sign in through two checkpoints and a pat-down search, or shoot your way past the guards.

Mike and Pete had taken the friendly approach at first, when they'd first started the full debriefing protocol. After all, he was cooperating fully and voluntarily. Why risk pissing him off and making him clam up?

"Okay, let's take it from the top." Mike smiled experimentally at the thin, hatchet-faced guy on the sofa while Pete hunched over the desk, fiddling with the interview recorder. Hatchet-face-Matt-nodded back, his expression serious. As well it should be, in his situation. Matt was an odd one; mid-thirties in age, with curly black hair and a face speckled with what looked like the remnants of bad acne, but built like a tank. He wore the same leather jacket and jeans he'd had on when he walked through the DEA office door.

"We're going to start the formal debriefing now you're here. When we've got the basics of your testimony down on tape, we'll escalate it to OCDTF and get them to sign off on your WSP participation and then set up a joint liaison team with the usual-us, the FBI, possibly FINCEN, and any other organizations whose turf is directly affected by your testimony. We can't offer you a blanket amnesty for any crimes you've committed, but along the way we'll evaluate your security requirements, and when we've got the prosecutions in train we'll be able to discuss an appropriate plea bargain for you, one that takes your time in secure accommodation here into account as time served. So you should be free to leave with a new identity and a clean record as soon as everything's wrapped up." He took a breath. "If there's anything you don't understand, say so. Okay?"

Matt just sat on the sofa, shoulders set tensely, for about thirty seconds, until Mike began to wonder if there was something wrong with him. Then: "You don't understand," he said, quietly but urgently. "If you treat this as a criminal investigation we will both die. They have agents everywhere and you have no idea what they are capable of." He had an odd foreign accent, slightly German, but with markedly softened sibilants.

"We've dealt with Mafia families." Mike smiled encouragingly.

"They are not your Mafia." Matt stared at him. "You are at war. They are a government. They will not respond as criminals, but as soldiers and politicians. I am here to defect, but if you are going to insist that they are ordinary criminals, you will lose."

"Can you point to them on a map?" Mike asked, rhetorically. The informer shook his head. He looked faintly-disappointed? Amused? Annoyed? Mike felt a stab of hot anger. Stop playing head games with me, he thought, or you'll be sorry.

Pete looked up. "Are we talking terrorists here? Like Al-Qaida?" he asked.

Matt stared at him. "I said they are a government. If you do not understand what that means we are both in very deep trouble." He picked up the cigarette packet on the table and unwrapped it carefully. His fingers were long, but his nails were very short. One was cracked, Mike noticed, and his right index finger bore an odd callus: not a shooter's finger, but something similar.

"There is more than one world," Matt said carefully as he opened the packet and removed a king-size. "This world, the world you are familiar with. The world of the United States, and of Al-Qaida. The world of automobiles and airliners and computers and guns and antibiotics. But there is another world, and you know nothing of it."

He paused for a moment to pick up the table lighter, then puffed once on the cigarette and laid it carefully on the ashtray.

"The other world is superficially like this one. There is a river not far from here, for example, roughly where the Charles River flows. But there is no city. Most of Boston lies under the open sea. Cambridge is heavily forested.

"There are people in the other world. They do not speak your language, this English tongue. They do not worship your tree-slain god. They don't have automobiles or airliners or computers or guns or antibiotics. They don't have a United States. Instead, there are countries up and down this coast, ruled by kings."

Matt picked up the cigarette and took a deep lungful of smoke. Mike glanced over at Pete to make sure he was recording, and caught a raised eyebrow. When he looked back at Matt, careful to keep his expression blank, he realized that the informant's hands were shaking slightly.

"It's a nice story," he commented. "What has it got to do with the price of cocaine?"

"Everything!" Matthias snapped.

Taken aback, Mike jerked away. Matt stared at him: he stared right back, nonplussed. "What do you mean?"

After several seconds, Matthias's tension unwound. "I'm sorry. I will get to the point," he said. "The kingdom of Gruinmarkt is dominated by a consortium of six noble houses. Their names are-no, later. The point is, some members of the noble bloodline can walk between the worlds. They can cross over to this world, and cross back again, carrying… goods."

He paused, expectantly.

"Well?" Mike prodded, his heart sinking. Jesus, just what I need. The hottest lead this year turns out to be a card-carrying tinfoil hat job.