He glanced at his watch. Less than a minute had passed. Should he call back and tell the unit to roll up silently? He didn't know. There were probably procedures for handling this sort of situation – procedures that cops like Frank Bishop and Bob Shelton would surely know well. Anderson was used to a very different kind of police work. Hisstakeouts were conducted sitting in vans, staring at the screen of a Toshiba laptop connected to a Cellscope radio directional-finding system.

Then he remembered: his weapon…

He looked down at the chunky butt of the Clock. He pulled it off his hip and pointed it downward, finger outside the trigger, as he vaguely remembered he ought to do.

Then, through the mist, he heard a faint electronic trill.

The killer had gotten a phone call. He pulled a cell phone off his belt and held it to his ear. He glanced at his watch, spoke a few words. Then he put the phone away and turned back the way he'd come.

Hell, he's going back to his car, the detective thought. I'm going lose him…

Ten minutes till the backup gets here. Jesus…

Andy Anderson decided he had no choice. He was going to do something he'd never done: make an arrest alone.

Anderson moved next to a low bush. The killer was walking quickly along the path, hands in his pockets.

That was good, Anderson decided – the hands encumbered, which would make it more difficult to get to the knife.

But wait, he wondered: What if he was hiding a pistol in his pocket?

Okay, keep that in mind.

And remember too that he might have Mace or pepper spray or tear gas.

And remember that he might simply turn and sprint away. The cop wondered what he'd do then. What were the fleeing felon rules? Could he shoot the killer in the back?

He'd busted dozens of criminals but he'd always been backed up by cops like Frank Bishop, for whom guns and high-risk arrests were as routine as compiling a program in C++ was for Anderson.

The detective now moved closer to the killer, thankful the rain was obscuring the sound of his footsteps. They were paralleling each other now on opposite sides of a row of tall boxwood. Anderson kept low and squinted through the rain. He got a good look at the killer's face. An intense curiosity coursed through him: What made this young man commit the terrible crimes he was responsible for? This curiosity was similar to what he felt when examining software code or puzzling over the crimes CCU investigated – but it was stronger now because, though he understood the principles of computer science and the crimes that that science made possible, a criminal like this was a pure enigma to Andy Anderson.

Except for the knife, except for the gun he might or might not be clutching in his hidden hand, the man seemed benign, almost friendly.

The detective wiped his hand on his shirt to dry some of the rain and gripped the pistol firmly once more. He continued on. This's a hell of a lot different from taking down hackers at a public terminal in the mall or serving warrants in houses where the biggest dangers were the plates of putrid food sitting stacked next to a teenager's machine.

Closer, closer…

Twenty feet farther on, their paths would converge. Soon Anderson would have no more cover and he'd have to make his move.

For an instant his courage broke and he stopped. He thought of his wife and daughter. And how alien he felt here, how completely out of his depth he was. He thought: Just follow the killer back to his car, get the license plate and follow as best you can.

But then Anderson thought of the deaths this man had caused and the deaths that he'd cause again if not stopped. This might be their only chance to capture him.

He started forward again along the path that would intersect with the killer's.

Ten feet.

Eight…

A deep breath.

Watch the hand in the pocket, he reminded himself.

A bird flew close – a gull – and the killer turned to look at it, startled. He laughed.

And that was when Anderson burst from the bushes, shoving the pistol toward the killer, shouting, "Freeze! Police! Hand out of your pocket!"

The man spun around to face the detective, muttering, "Shit." He hesitated for a moment.

Anderson brought the gun even with the killer's chest. "Now! Move slow!"

The hands appeared. Anderson stared at the fingers. What was he holding?

He almost laughed. It was a rabbit's foot. A lucky key chain.

"Drop it."

He did and then lifted his hands in the resigned, familiar way of someone who's been through an arrest before.

"Lie down on the ground and keep your arms spread."

"Jesus," the man spat out. "Jesus. How the fuck did you find me?"

"Do it," Anderson shouted in a quaking voice.

The killer lay down on the ground, half on the grass and half on the sidewalk. Anderson was kneeling over him, shoving his gun into the man's neck as he put the cuffs on, an awkward feat that took several tries. He then frisked the killer and relieved him of the Ka-bar knife and cell phone and wallet. He had been carrying a small pistol, it turned out, but that had been in the pocket of his jacket. The weapons, wallet, phone and rabbit's foot went into a pile on the grass nearby. Anderson stepped back, his hands shaking from the adrenaline.

"Where the fuck d'you come from?" the man muttered.

Anderson didn't respond but just stared at his prisoner as the shock of what he'd done was replaced with euphoria. What a story he'd have to tell! His wife would love it. He wanted to tell his little daughter but that would have to wait a few years. Oh, and Stan, his neighbors, who -

Then Anderson realized that he'd forgotten the Miranda warning. He didn't want to blow an arrest like this by making a technical mistake. He found the card in his wallet and read the words stiffly.

The killer muttered that he understood his rights.

"Officer, you okay?" a man's voice called. "You need any help?"

Anderson glanced behind him. It was the businessman he'd seen under the awning. His dark suit, expensive-looking, was dampened by the rain. "I've got a cell phone. You need to use it?"

"No, no, that's okay, everything's under control." Anderson turned back to his prisoner. He holstered his weapon and pulled out his own cell phone to report in. He hit redial but for some reason the call wouldn't go through. He glanced at the screen and the phone reported, NO SIGNAL.

That was odd. Why -

And in an instant – an instant of pure horror – he realized that no street cop in the world would've let an unidentified civilian get behind him during an arrest. As he groped for his pistol and started to turn, the businessman grabbed his shoulder and the detective felt an explosion of pain in his back.

Anderson cried out and dropped to his knees. The man stabbed him again with his own Kabar knife.

"No, please, no…"

The man lifted away Anderson 's gun and kicked him forward onto the wet sidewalk.

He then walked over to the young man Anderson had just handcuffed. He rolled him over on his side and looked down.

"Man, I'm fucking glad you're here," the cuffed man said. "This guy comes out of nowhere and I thought I was fucked. Get me out of these things, will you? I -

"Shhhh," the businessman said and turned back to the CCU cop, who was struggling to reach the terrible pain in his back, trying to touch it. If he could only touch it then the searing agony would go away.

The attacker crouched down next to him.

"You're the one," Anderson whispered to the businessman. "You killed Lara Gibson." His eyes flicked to the man he'd handcuffed. "And he's Fowler."

The man nodded. "That's right." Then he said, "And you're Andy Anderson." The awe in his voice was genuine. "I didn't think it'd be you coming after me. I mean, I knew you worked for the Computer Crimes Unit and'd be investigating the Gibson case. But not here, not in the field. Amazing… Andy Anderson. You're a total wizard."