"That fits," Gentry said. "They came out of the first cause, When It Changed. You already figured that. But you don't know what happened yet, do you?"

"No. I just know where. Straylight. She's told me all that part, I think all she knows. Doesn't really care about it. Her mother put together a couple of AIs, very early on, real heavy stuff. Then her mother died and the AIs sort of stewed in the corporate cores, up there. One of them started doing deals on its own. It wanted to get together with the other one ... "

"It did. There's your first cause. Everything changed."

"Simple as that? How do you know?"

"Because," Gentry said, "I've been at it from another angle. You've been playing cause and effect, but I've been looking for outlines, shapes in time. You've been looking all over the matrix, but I've been looking at the matrix, the whole thing. I know things you don't."

Bobby didn't answer. Slick turned from the window and saw the girl, the same one, standing across the room. Just standing there.

"It wasn't just the Tessier-Ashpool AIs," Gentry said. "People came up the well to crack the T-A cores. They brought a Chinese military icebreaker."

"Case," Bobby said, "Guy named Case. I know that part. Some kind of synergistic effect ... "

Slick watched the girl.

"And the sum was greater than the parts?" Gentry really seemed to be enjoying this. "Cybernetic godhead? Light on the waters?"

"Yeah," Bobby said, "that's about it."

"It's a little more complicated than that," Gentry said, and laughed.

And the girl was gone. No click.

Slick shivered.

Night fell during the Underground's peak evening traffic, though even then it was nothing like Tokyo, no shiroshi-san struggling to wedge a last few passengers in as the doors were closing. Kumiko watched the salmon haze of sunset from a windy platform on the Central Line, Colin lounging against a broken vending machine with a row of cracked, dusty windows. "Time now," he said, "and keep your head demurely down through Bond Street and Oxford Circus."

"But I must pay, when I leave the system?"

"Not everyone does, actually," he said, tossing his forelock.

She set off for the stairs, no longer requiring his directions to find her way to the opposite platform. Her feet were very cold again, and she thought of the fleece-lined German boots in the closet in her room at Swain's. She'd decided on the combination of the rubber toe-socks and the high French heels as a ploy to lull Dick, to make him doubt she'd run, but with each bite of cold through the thin soles she regretted the idea.

In the tunnel to the other platform, she relaxed her grip on the unit and Colin flickered out. The walls were worn white ceramic with a decorative band of green. She took her hand from her pocket and trailed her fingers along the green tiles as she went, thinking of Sally and the Finn and the different smell of a Sprawl winter, until the first Dracula stepped smartly in front of her and she was instantly and very closely surrounded by four black raincoats, four bone-thin, bone-white faces. " 'Ere," the first one said, "innit pretty."

They were eye to eye, Kumiko and the Dracula; his breath smelled of tobacco. The evening crowd continued on its way around them, bundled for the most part in dark wool.

"Oo," one said, beside her, "look. Wot's this?" He held up the Maas-Neotek unit, his hand gloved in cracked black leather. "Flash lighter, innit? Let's 'ave a snag, Jap." Kumiko's hand went to her pocket, shot straight through the razor slash, and closed on air. The boy giggled.

"Snags in 'er bag," another said. " 'Elp 'er, Reg." A hand darted out and the leather strap of her purse parted neatly.

The first Dracula caught the purse, whipped the dangling strap around it with a practiced flick, and tucked it into the front of his raincoat. "Ta."

" 'Ere, she's got 'em in 'er pants!" Laughter as she fumbled beneath layered sweaters. The tape she'd used hurt her stomach as she tore the gun free with both hands and flipped it up against the cheek of the boy who held the unit.

Nothing happened.

Then the other three were racing frantically for the stairs at the far end of the tunnel, their high-laced black boots slipping in melted snow, their long coats flapping like wings. A woman screamed.

And still they were frozen there, Kumiko and the Dracula, the muzzle of the pistol pressed against his left cheekbone. Kumiko's arms began to tremble.

She was looking into the Dracula's eyes, brown eyes gone wide with an ancient simple terror; the Dracula was seeing her mother's mask. Something struck the concrete at her feet: Colin's unit.

"Run," she said. The Dracula convulsed, opened his mouth, made a strangled, sobbing sound, and twisted away from the gun.

Kumiko looked down and saw the Maas-Neotek unit in a puddle of gray slush. Beside it lay the clean silver rectangle of a single-edged industrial razorblade. When she picked up the unit, she saw that its case was cracked. She shook moisture from the crack and squeezed it hard in her hand. The tunnel was deserted now. Colin wasn't there. Swain's Walther air pistol was huge and heavy in her other hand.

She stepped to a rectangular receptacle fastened to the tile wall and tucked the gun down between a grease-flecked foam food container and a neatly folded sheaf of newsfax. Turned away, then turned back for the fax.

Up the stairs.

Someone pointed at her, on the platform, but the train roared in with its antique clatter and then the doors slid shut behind her.

She did as Colin had instructed, White City and Shepherd's Bush, Holland Park, raising the fax as the train slowed for Notting Hill -- the King, who was very old, was dying -- and keeping it there through Bond Street. The station at Oxford Circus was very busy and she was grateful for the sheltering crowd.

Colin had said that it was possible to leave the station without paying. After some consideration, she decided that this was true, though it required speed and timing. Really, there was no other way; her purse, with the MitsuBank chip and her few English coins, had gone with the Jack Draculas. She spent ten minutes watching passengers surrender their yellow plastic tickets to the automated turnstiles, took a deep breath, and ran. Up, over, behind her a shout and a loud laugh, and then she was running again.

When she reached the doors at the top of the stairs, she saw Brixton Road waiting like a tatty Shinjuku, jammed with steaming foodstalls.