Fireproof

gasoline was refined and possibly where it was distributed from?” Racine asked.
    “In some cases the chemical breakdown can be so accurate we’ve been able to identify and trace the gasoline to a specific gas station. In one case we were able to trace it to a particular vehicle.”
    “Smells like diesel,” Maggie said, walking around Ganza’s van.
    Tully sniffed the air. Smelled like the bottom of his kitchen oven. One of these days he needed to learn how to clean that burned crispy gunk that stuck to the rack.
    “Good nose,” Ganza said. “If it is diesel that’ll explain why the body didn’t burn. Diesel fuel is combustible, not flammable. Doesn’t burn as easily. Soaks in or dissipates before giving off enough vapor to ignite. Also narrows it down a bit. Not as many inner cities sell diesel. But the interstate is close by.”
    “Interesting choice. Why make harder for him and easier for us?” Racine asked.
    “Maybe he just used what was handy,” Tully guessed. “Most criminals don’t go out of their way to buy something special. They use what’s available. What they already have.”
    “Or find at the scene,” Maggie added.
    “But someone who’s done it before and is most likely planning on doing it again?” Racine didn’t buy their explanation. “Wouldn’t he be more careful?”
    “Serial criminals don’t expect to be caught,” Maggie told her. “The fact that they’ve gotten away with it several times usuallymakes them more reckless, not more cautious.” She turned toward the alley. “Can you show me exactly where the body was?”
    Tully led the way. Everyone else had gone. Ganza was the last to collect his samples. That’s why the movement at the other end of the alley was so easy to spot.
    The man was hunched down, sneaking underneath the rusted stairs of a fire escape, staying along the far wall. He was about twenty feet from the alley’s exit. He froze and stayed low in the shadows, apparently unaware that Tully had seen him.
    Maggie thumped the back of her hand into Tully’s arm. Racine stopped cold.
    “So the body was by the Dumpster,” Maggie said casually, keeping her gait steady, her voice even.
    Each of their steps came with a crunch, telegraphing their approach. Had the arsonist come back? It wouldn’t be the first time. He must have been waiting around and thought they were finally finished.
    Racine reached inside her jacket. Maggie touched her elbow and shook her head. She waved her thumb over her shoulder and Racine got the hint.
    “Hey, I’ve got to make a call,” she said. “I’ll catch up with you two later.”
    She turned a bit too quickly on the balls of her feet, but otherwise Tully thought she did a fine acting job. Racine had just cleared the corner to the entrance when they got to the Dumpster.
    The guy started slithering along the wall again, and Tully wanted to stop him. If he got to the exit a few strides ahead, he might get away. Tully tried to remember what was on the other side of the alley. Another street. He could hear the traffic.
    He didn’t need to make the decision. The guy stood and broke into a full-throttled run. Tully did, too. The guy was fast. Not so fast that he couldn’t sling a backpack under Tully’s feet, and Tully came down hard. His elbow smashed against the pavement with a sick crack. Pain shot up his shoulder, all the way to his back molars.

CHAPTER 22

    Maggie hurdled over Tully’s long sprawled legs. She glanced back and heard him yell, “Go, go. I’m okay.”
    His face was contorted in pain and Maggie knew he wasn’t okay, but she kept going.
    “FBI, stop,” she yelled at the man as he got to the end of the alley.
    He didn’t even flinch. Slowed just enough to skid around the corner.
    Maggie followed. Depending on which building Racine was coming around it could be Maggie’s footrace to lose.
    The man looked over his shoulder. He saw how close she was and jolted into the street. He danced through traffic. Brakes screeched. Horns blasted. The hydraulics of a Metro bus whined and the man bounced off its bumper. He didn’t look hurt. If anything, it had propelled him a few steps more ahead of her.
    Once back on the sidewalk the guy broke into a sprint, weaving and shoving his way through. There weren’t many people. Most were homeless. They moved slowly or simply stood and watched. Maggie was a runner, tracking ten to twenty miles a week. Ordinarilythis footrace would be a cakewalk. Not today. The thump