“Josie?” he asked, trying to fit together the pieces. “Where is she?”

“Asleep. I gave her a sleeping pill.”

“You want to talk about it?”

“We saw Jordan McAfee today, and Josie told him…she told him that she remembered something about the shooting. In fact, she remembered everything.”

Patrick whistled softly. “So she was lying?”

“I don’t know. I think she was scared.” Alex glanced up at Patrick. “That’s not all. According to Josie, Matt shot at Peter first.”

“What?”

“The knapsack Peter was carrying fell down in front of Matt, and he got hold of one of the guns. He shot, but he missed.”

Patrick rubbed a hand down his face. Diana Leven was not going to be happy.

“What’s going to happen to Josie?” Alex said. “The best-case scenario is that she gets on the stand and the entire town hates her for testifying on Peter’s behalf. The worst-case scenario is that she commits perjury on the stand and gets charged with it.”

Patrick’s mind was racing. “You can’t worry about this. It’s out of your hands. Besides, Josie will be fine. She’s a survivor.”

He leaned down and kissed her, softly, his mouth rounding over words he couldn’t yet tell her, and promises he was afraid to make. He kissed her until he felt the tightness go out of her spine. “You ought to go take one of those sleeping pills,” he whispered.

Alex tilted her head. “You’re not staying?”

“Can’t. I’ve still got work to do.”

“You came all the way over here to tell me you’re leaving?”

Patrick looked at her, wishing he could explain what he had to do. “I’ll see you later, Alex,” he said.

Alex had confided in him, but as a judge, she would know that Patrick could not keep her secret. On Monday morning, when Patrick saw the prosecutor, he’d have to tell Diana what he now knew about Matt Royston firing the first shot in the locker room. Legally, he was obligated to disclose this new wrinkle. However, technically, he had all day Sunday to do with that information whatever he liked.

If Patrick could find evidence to back up Josie’s allegations, then it would soften the blow for her on the stand-and make him a hero in Alex’s eyes. But there was another part of him that wanted to search the locker room again for another reason. Patrick knew he had personally combed that small space for evidence, that no other bullet had been found. And if Matt had shot first at Peter, there should have been one.

He hadn’t wanted to say this to Alex, but Josie had lied to them once. There was no reason she couldn’t be doing it again.

At six in the morning, Sterling High School was a sleeping giant. Patrick unlocked the front door and moved through the corridors in the dark. They had been professionally cleaned, but that didn’t stop him from seeing, in the beam of his flashlight, the spots where bullets had broken windows and blood had stained the floor. He moved quickly, the heels of his boots echoing, as he pushed aside blue construction tarps and avoided stacks of lumber.

Patrick opened the double doors of the gym and squeaked his way across the Morse-coded markings on the polyurethaned boards. He flicked a bank of switches and the gym flooded with light. The last time he’d been in here, there had been emergency blankets lying on the floor, corresponding to the numbers that had been inked on the foreheads of Noah James and Michael Beach and Justin Friedman and Dusty Spears and Austin Prokiov. There had been crime-scene techs crawling on their hands and knees, taking photographs of chips in the cement block, digging bullets out of the backboard of the basketball hoop.

He had spent hours at the police station, his first stop after leaving Alex’s house, scrutinizing the enlarged fingerprint that had been on Gun B. An inconclusive one; one that he’d assumed, lazily, to be Peter’s. But what if it was Matt’s? Was there any way to prove that Royston had held the gun, as Josie claimed? Patrick had studied the prints taken from Matt’s dead body and held them up every which way against the partial print, until the lines and ridges blurred even more than they should have.

If he was going to find proof, it was going to have to be in the school itself.

The locker room looked exactly like the photo he’d used during his testimony earlier this week, except that the bodies, of course, had been removed. Unlike the corridors and classrooms of the school, the locker room hadn’t been cleaned or patched. The small area held too much damage-not physical, but psychological-and the administration had unanimously agreed to tear it down, along with the rest of the gym and the cafeteria, later this month.

The locker room was a rectangle. The door that led into it, from the gym, was in the middle of one long wall. A wooden bench sat directly opposite, and a line of metal lockers. In the far left corner of the locker room was a small doorway that opened into a communal shower stall. In this corner, Matt’s body had been found, with Josie lying beside him; thirty feet away in the far right corner of the locker room, Peter had been crouching. The blue backpack had fallen just to the left of the doorway.

If Patrick believed Josie, then Peter had come running into the locker room, where Josie and Matt had gone to hide. Presumably, he was holding Gun A. He dropped his backpack, and Matt-who would have been standing in the middle of the room, close enough to reach it-grabbed Gun B. Matt shot at Peter-the bullet that had never been found, the one that proved Gun B was fired at all-and missed. When he tried to shoot again, the gun jammed. At that moment, Peter shot him, twice.

The problem was, Matt’s body had been found at least fifteen feet away from the backpack where he’d grabbed the gun.

Why would Matt have backed up, and then shot at Peter? It didn’t make sense. It was possible that Peter’s shots had sent Matt’s body recoiling, but basic physics told Patrick that a shot fired from where Peter was standing would still not have landed Matt where he’d been found. In addition, there had been no blood-spatter pattern to suggest that Matt had been standing anywhere near the backpack when he was hit by Peter. He’d pretty much dropped where he’d been shot.

Patrick walked toward the wall where he’d apprehended Peter. He started at the upper corner and methodically ran his fingers over every divot and niche, over the edges of the lockers and inside them, around the bend of the perpendicular walls. He crawled beneath the wooden bench and scrutinized the underside. He held his flashlight up to the ceiling. In such close quarters, any bullet fired by Matt should have made enough serious damage to be noticeable, and yet, there was absolutely no evidence that any gun had been fired-successfully-in Peter’s direction.

Patrick walked to the opposite corner of the locker room. There was still a dark bloodstain on the floor, and a dried boot print. He stepped over the stain and into the shower stall, repeating the same meticulous investigation of the tiled wall that would have been behind Matt.

If he found that missing bullet here, where Matt’s body had been found, then Matt clearly hadn’t been the one to fire Gun B-it would have been Peter wielding that weapon, as well as Gun A. Or in other words: Josie would have been lying to Jordan McAfee.

It was easy work, because the tile was white, pristine. There were no cracks or flakes, no chips, nothing that would suggest a bullet had gone through Matt’s stomach and struck the shower wall.

Patrick turned around, looking in places that didn’t make sense: the top of the shower, the ceiling, the drain. He took off his shoes and socks and shuffled along the shower floor.

It was when he’d just scraped his little toe along the line of the drain that he felt it.

Patrick got down on his hands and knees and felt along the edge of the metal. There was a long, raw scuff on the tile that bordered the drainage grate. It would have easily gone unnoticed because of its location-techs who saw it had probably assumed it was grout. He rubbed it with his finger and then peered with a flashlight into the drain. If the bullet had slipped through, it was long gone-and yet, the drainage holes were tiny enough that this shouldn’t have been possible.