Arnie Becker, the forty-three-year-old lead arson investigator attached to the Bureau of Fire Investigation, arrived with the second-alarm unit. In situations like this, Becker's task was to determine the origin of the blaze. To do that, he'd have to enter the building and investigate all the indicators-"V" patterns on walls, decalcification of Sheetrock, "alligatoring" of studs, condition of electrical components and so on-and by doing so, hope to locate the spot where the fire began, and if possible determine what might have caused it.

Becker was a twenty-year veteran of the fire department. In San Francisco his whole working life, he was particularly familiar with Victorians, and he knew that this house, with all the places in which a fire could hide, would in all likelihood burn through the night and perhaps well into the next morning. He wasn't going to have an answer anytime soon.

But that didn't mean he didn't have a lot to do. A huge crowd of onlookers had coalesced on the block, and more were streaming out of houses both up and down the street and across the open space of Alamo Square behind them. This was his potential witness pool-people he and his team would need to talk to. Some percentage of them might live on the block, might have seen something suspicious.

He needed all the information he could find from a near-infinite universe of possibilities, the most tantalizing one being that if this fire was arson, if someone had started it, then that person was probably among the crowd, enjoying his handiwork, possibly even sitting in one of the cypress trees in Alamo Square getting sexual satisfaction from it. Becker had seen it before.

In San Francisco, police officers from the hit-and-run detail are assigned to fire investigation, so Becker had a staff of helpers and he sent them out to talk to everybody they could. They would not conduct formal interviews-not now, anyway-but he wanted names and phone numbers of everybody. If people didn't want to provide that, that could be instructive. If still others wouldn't shut up, that might tell him something as well. Becker didn't know anything, including what he didn't know. So this was his chance to start gathering information from whatever source presented itself, and he took it very seriously indeed. His men fanned out to either end of the crowd and were working it to the inside and from behind.

Becker himself was on his way to talk to the neighbor who'd called in the fire and who had waited around to help guide the trucks when they'd arrived, not that they had needed it by then. But suddenly Becker's partner in the Arson Unit, J. P. Dodd-twenty-eight years old, Army-trained, competent yet relaxed, appeared at his elbow. The night around them was a kaleidoscope of lights in the darkness-the yellow flickering fire, the red bubbles on the trucks, the white glare from the firemen's helmets, now the kleigs of the TV camera crews. Dodd's earnest face looked particularly grave. "They've found two bodies, Arn. Shaklee needs you to come on up."

The fire still raged in the back of the house and on the upper stories. The two manned fire hoses at the front door snaked across the floor of the foyer and disappeared out the right-hand doorway somewhere back into the inferno. Becker, now suited up in his turnout coat and night helmet, his Scotts down over his face, also held a wide-beam flashlight that he trained on the bodies. He squatted like a baseball catcher, having learned that to put a knee on the floor was an invitation to pain and suffering.

The clothing had been burned off where they had been exposed, but even though both figures were lying on their backs, he couldn't tell what sex either had been. One was larger, and one smaller, so they were possibly a man and a woman, but he wouldn't be sure until the coroner was finished with them. The hair and any distinguishing characteristics on the faces, likewise, were burned away.

Something in the resting attitudes struck him, though. He had seen many dead people before, the victims of fire, as well as victims of murder and/or suicide, who were at fire scenes but dead before they burned. In his experience, the bodies of people who died from fire or smoke inhalation as the blaze grew around them tended to curl protectively into a fetal position. Victims of murder or suicide most often lay as they fell, and these two bodies fit that profile. There was still the characteristic drawing up of the extremities as the flesh cooked, but it did not strongly resemble the curled-up bodies he'd seen of victims who'd died by fire and fire alone.

Suspicious by nature and now by circumstance, Becker reached for a flashlight-like device he wore on his belt- the multi-gas-detecting AIM-32/50. Turning it on, he waved it down the sides of the smaller victim-the one nearest to the front door-and wasn't exactly stunned to see that it registered the presence of gasoline.

So, Becker thought, this was probably arson. And from the attitudes of the bodies, it was quite possibly a murder, or a murder/suicide, as well.

Becker tucked in his gas detector, then trained his flashlight again on the smaller body in front of him. Directly over his head, a deafening crash shook the building and rained charcoal down over him, but he barely heard or noted it. The small and perfectly round hole high in the back of the head, above and behind where the ear should have been located-it had burned away-commanded all of his attention. Stepping over the smaller torso, Becker moved over the still-squishy rug, squatted and shone his light on the other victim. Tucked under the side of the torso, a glint of metal shone up when his beam hit it. Becker wasn't going to touch anything at this point, but he lowered his light's trajectory and saw enough to realize that he was looking at the barrel of a gun.

At a little after eleven p.m., Inspector Sergeant Dan Cuneo of San Francisco's homicide detail parked his unmarked car on the opposite side of Alamo Square and began to make his way through the large, awestruck, worried crowd. His immediate sense was that this fire was nowhere near to being controlled. Three houses on the block now appeared to be burning, and in the crowd he overheard snatches of panicked conversations, some from what must have been residents. People staring mesmerized, some crying, some talking in hushed tones. As he came closer, he noticed a cordoned-off command area on the steps up the street that led into the park.

Cuneo knew where he needed to go, and he made a beeline toward the white helmet that seemed to hover above the crowd. The white helmet belonged to the incident commander. Every fire scene had an IC, and his power within that setting was absolute. The president of the United States could show up at a fire, wanting to get a better look, and the IC could order him to chill for a while and that would be the end of the discussion.

Cuneo got close enough to make out some of the faces that had gathered around this IC-the name tag over his left pocket said "Shaklee." He was taller than Cuneo's own six feet. Cuneo pushed his way through the crowd, excused himself and presented his badge. Shak-lee nodded distractedly, said something into his walkie-talkie, came back to Cuneo. "You need to see Becker." He pointed toward the steps. "The guy talking to the woman in the leather jacket."

Cuneo nodded his thanks and started walking over. He was an edgy man in his early forties, unable to keep still or quiet-he could not eat or listen to a witness or a colleague without humming-and this trait had kept him from retaining a regular partner in homicide. For the past year or more, he'd been working strictly solo. His fellow inspectors considered him a character, but not quite a weirdo. It was a critical distinction.

Handsome in an unusual way, Cuneo's face had an oddly misshapen character as well, almost as though it had once been broken down to its integral pieces and then imperfectly reassembled. His nose initially protruded to a ridge, then hooked left and went flat as though someone had pushed it in like a thumbtack. At times he appeared cross-eyed. He'd obviously survived a serious bout with teenage acne, but instead of scarring, the skin over his cheeks had taken on a stretched, almost shiny look-maybe too many skin peels. An inventory of the individual parts wouldn't indicate it, but somehow the mishmash came together in a way that pleased his girlfriends.