All he could think about was that.40. At least two kids killed with the same weapon. Evidence from shots-fired in different parts of the city linked to the same gun. A stash gun. He needed to clear his head. He needed to connect the dots.

Mooney put down the stack of reports and stood up from the table. He walked to the window and looked down at the few cars passing by on Tremont Street. It was after ten o’clock. They had gone through most of the old files. He’d had enough of sitting around reading reports and looking at pictures. He had missed being at the crime scene the night before. A Sunday night, and he’d been home watching the opening games of the football season. Only twenty-four hours ago, he’d been assigned to Evidence Management. Working days. “Let’s go,” he said. “I want to see where he left Courtney and Josh.”

It was great working with Angel Alves again. He was young enough to believe he could solve every case and had the energy to follow through. His energy was catchy, but Mooney had to keep him focused. Mooney was primed for the long night ahead.

“Any idea how he picks his victims?” Alves asked as he started the Ford.

“After Kelly and Eric? I don’t know. This city’s full of college kids. He could have run into the others, walking after dinner, outside a club, after a party. We had some info that one of the couples-Daria and David-used to go parking up on Chickatawbut Road in the Blue Hills.”

“Mostly gay guys cruising up there, and it’s outside the city.”

“The staties helped us. We sat on it for a few weeks. Kept an eye on some of the regulars and stopped a few to FIO them, get their names and addresses. They must have spread the word. Within two days we were watching squirrels and raccoons. Six murders, bodies at three different sites, and we had nothing.”

“Just like we have now,” Alves said.

“Did you know there’s a website devoted to this guy? Promnightkiller.com. A bunch of conspiracy theorists speculating about who the killer is and why he stopped killing. Most of them think he’s still out there. Like the Jack the Ripper theorists-they believe the killer is some powerful politician’s relative and the police are covering it up. The website must be buzzing tonight.”

“I’ll talk to the guys at the BRIC about monitoring the site,” Alves said. “They track everything going on in the city. A great resource on shooting cases. It’s not just intel, they’ve also got the Shot Spotter. Within seconds of a gunshot, the system pulls up aerial images and uses triangulation to show where the shots came from. The cameras set up around the city tie into the system and provide video of that area at the time of the shots. It’s a great way to get an ID on a suspect or to eliminate someone as a suspect.”

“Sounds good on paper.” Mooney was staring straight ahead.

“It’s not perfect. They’re still working out the kinks. And there aren’t enough cameras set up around the city yet. Remember how we used to pull the jail tapes and listen to phone calls of guys in custody? The BRIC working with the Sheriff’s Department can set it up so that my cell phone will ring whenever a person of interest makes a call from jail. I can listen to the call live. Pretty amazing stuff.”

Anything was worth a shot. “So you think these guys at the BRIC can monitor the website?”

“They can. They might be able to tell if this guy’s trying to communicate on it. Maybe there are hints that he was going to kill again.”

“It’s worth a try, but I don’t think this guy is one to communicate. We tried to draw him out, but he never left any messages outside of the fortunes.”

“We need to get him in a dialogue. Maybe we can have someone at the BRIC get involved in an online chat on the website. Have him say that he thinks the recent killings are the work of a copycat. That this guy is an amateur, not the real Prom Night Killer.”

“So we piss him off and get him to convince us he’s the real killer.” Mooney recognized the sound principle behind this gambit. Serial killers always thought they were smarter than the cops. They wanted the last word.

“What if he tries to convince us by killing two more kids?” Angel asked.

“That’s always a possibility.” Mooney lifted a photo of Courtney Steadman and Josh Kipping, studying it. “But that’s a risk we have to take.”

Alves parked along the access road, near the tennis courts. The park was dark. A blanket of grass led to the baseball diamond and, beyond that, the fairway. A darker sweep led to a hill, rising against the night sky, ragged and forbidding.

It had been quiet. No arrests. They’d spent most of the night looking for Tinsley, circling the streets of Grove Hall, an area of Roxbury with old mansions with widow’s walks and stained glass, a neighborhood now plagued with drugs and violent crime. Connie had been to crime watches and community meetings. He’d met families living in the same houses for generations who refused to give up their neighborhood to a few bad actors.

“What are the names Ward gave us?” Ahearn asked.

“Michael Rogers and Ellis Thomas,” Connie said. “You know them?”

Ahearn shook his head, focusing on the dark road ahead.

Greene said, “I ran their BOPs. Thomas is clean. Never been arrested. Rogers is another story. Looks like he’s putting himself in the mix, cafeteria-style offenses. Little of this, little of that. Possession of weed, shoplifting, disorderly, resisting, that kind of crap. Next thing you know he’s sticking kids up at school, stealing cars. Had a gun charge dismissed. Backseat passenger in a car that belonged to the driver’s girlfriend. Gun in the glovy. I’m thinking he’s a crash test dummy, trying to earn some respect, get himself a reputation on the street.”

“If this kid wants to keep building his résumé, then he’s got to establish himself as a shooter,” Connie said.

“Jackie,” Greene said, “If we see anyone hanging out, we’ll stop and FIO them, get their personal info, see what they’re up to. Don’t let on who we’re looking for or why. We don’t want anyone going after Ward for being a snitch. If we find Rogers and Thomas, we’ll pull them aside and see if we can get anything. If not, we’ll hit them with the subpoenas. Sound good, Connie?”

“That’s a plan.”

Ahearn turned the car at a ninety-degree angle to the curb, lights on the sidewalk. Connie followed them out of the unmarked cruiser. They walked toward a group standing in front of them. A small shrine of burning candles flickered in the night. A pile of teddy bears honored the most recent homicide victim. Not ten feet away was another shrine, the toys washed out from sun and rain, the votives filled with old rainwater. On the corner was a small store, the brick façade painted with a mural dedicated to the “fallen heroes” of the neighborhood. Connie recognized the faces, gang members that had terrorized the area. Now they would be remembered as innocent victims of gun violence, the familiar RIP painted over their images.

There were eight of them gathered there, mostly teenagers. And two older guys. One of them was dark-skinned, maybe thirty. Maybe one of the OGs. But he was dressed too sharp. Buttoned-down oxford shirt, sports jacket, slacks, and spit-shined shoes. Connie had seen him before, but he couldn’t place the man’s face.

Then there was the white guy.

He really didn’t fit in the picture. He was short, a little over five feet, dressed in jeans and a windbreaker. At first, Connie thought he might be a junkie looking to make a score, but he looked too clean to be a fiend. If he wasn’t there to buy drugs, what was he doing on Magnolia Street in the middle of the night?

They were outnumbered almost three to one. Connie focused on everyone’s hands as he’d seen Angel Alves do. He laid back as the detectives approached the group.