I took off running. Cape Roane was a small town. The church and the lighthouse were separated by a matter of blocks.

“Call Lia,” I told Dean, “or Michael. Tell them we have to get back to Mackenzie.”

I didn’t wait for a response. I just hung up and kept running. I never should have left. It was part and parcel of being a profiler that I tended to get absorbed in cases. I’d been so focused on Kelley and her killer, but I never should have taken my eyes off Mackenzie. From the moment I’d realized that this killer liked to watch…

I should have known you’d be there. Watching.

The lighthouse was closer now, but not close enough. My sides were already starting to burn, my lungs beginning to tighten like a vise in my chest, but I managed to keep enough presence of mind to give my cell phone a verbal command.

“Call Celine.”

She answered, and I stopped running, just long enough to catch my breath—long enough to ask: “Mackenzie?”

“Everything is fine here.” Celine’s response was measured—unnaturally so. “The rain is a problem, but Mackenzie knows that, and we’re discussing next steps.”

I was soaked. Mackenzie must have been, too. And the ledge…

“You need to get her in,” I told Celine. “And if you can’t, you need to get her psychologist out of the room. Now.”

As I reached the lighthouse, I could hear a voice ringing in my mind. You can trust them, Mackenzie. We’ve talked about trust, haven’t we?

I’d thought the woman treating Mackenzie was incompetent. She’d said exactly the wrong thing at precisely the right moment to throw a kink in the works. If she’d kept her mouth shut, I could have talked Mackenzie down.

Maybe that was the point.

Thunder crashed, loud enough to jar my bones, but all I could think about was getting to Mackenzie.

Celine and our suspect met me halfway up the lighthouse stairs.

“Agent Delacroix said you needed a consult?” The psychologist didn’t sound annoyed, but her tone was brisk. “Something about adolescent depression?”

I glanced over at Celine. Apparently, she’d had to think on her feet to get the woman out of the room without causing a scene.

Point, Agent Delacroix.

“You should get back to Mackenzie,” I told Celine. “Let her know that Lia and I held up our end of the deal. She can come in.”

Tell her, I didn’t say, that I know who killed Kelley.

The psychologist stiffened. “If you’re going to be talking to Mackenzie,” she told Celine, “I should really be there.”

I stepped up, coming even with the woman. “Please,” I said. “This won’t take long, and it’s urgent.”

I could feel Celine looking at me. I was asking her to leave me alone with a woman I believed to be a killer. Under normal circumstances, she would have refused. Based on protocol, she should have.

But with the storm—with Mackenzie still out there—protocol was the least of our worries.

“Don’t worry,” Celine told me, even as her eyes said Be careful. “We’ll bring Mackenzie in.”

Celine returned the way she’d come, leaving me alone with the suspect. Now I just had to keep the suspect occupied long enough for Celine and the others to talk Mackenzie down.

Without interference this time.

Also, I thought, hyperaware of the space between my body and the killer’s next to me, I have to keep you talking long enough for my backup to arrive.

“We’re trying to get a handle on the motive behind the first two suicides,” I said, wishing Lia were here to sell the lie for me. “Is your practice focused on children Mackenzie’s age and younger, or do you treat older adolescents as well?”

“I primarily work with teenagers,” came the impatient response. “Mackenzie was referred to me by a colleague several months back. I’m afraid that without an in-depth look at your files I cannot comment on the specific cases you’re interested in. I can say, however, that children and adolescents have emotional lives every bit as complex as that of adults. Teenagers are individuals, not statistics. I could no more talk to you about a unified motive behind adolescent suicide than I could were we discussing adults.”

“I understand,” I said, also comprehending that unless I wanted to turn this into a confrontation, sans backup, I needed to give her something to stay for.

You’re drawn to pain. People with scars that run deep. The vulnerable ones, in need of your mercy.

“It wasn’t that long ago,” I said, laying the trap, “that I was a teenager myself.”

There was a moment’s pause, during which I registered exactly how narrow the stairs we were standing on were.

How easy it would be for her to push me.

“I have to confess, when you said you’d been working with the FBI since you were seventeen, I looked for the signs.”

Keep her talking, I thought. Give her what she wants.

“The signs of what?” I asked.

“Psychological trauma.” Her expression was neutral, but I could feel her stare crawling over my skin. “Working cases like Mackenzie’s when you were still a child yourself—that’s a lot to take on.”

Her tone was open, almost kind, and I remembered everything that Dean and I had concluded about our UNSUB from the files.

You see yourself as an angel of mercy. The first time you saw someone—or helped someone—commit suicide, they were probably in incredible pain, you probably loved them, and they might well have asked for your help.

You know trauma. You recognize it. Some part of you craves it.

Down below, I heard the door open and prayed that it was Lia—just like I prayed that up above, Celine and the crisis negotiator and Mackenzie’s mother had talked Mackenzie down.

“I really should be getting back to my patient.” The psychologist took a step up, positioning herself above me.

I said the only thing I could think of to stop her in her tracks. “I killed my mother.” You know trauma. You recognize it. You liberate the sufferer from it. “She made me do it, but it was my hand holding the knife.”

I only needed another minute, maybe two. I needed to distract her from the sound of footsteps running up the stairs toward us.

“I dream about it,” I said. “All of it, all the time.”

“I’m going back to Mackenzie.” Her voice was sharp, her movement up the stairs sudden.

I followed and grabbed for her arm. I’d offered her a taste of my pain. It wasn’t enough to keep her here—but I had to keep her away from Mackenzie.

“Let me go.”

“Did you treat the Summers boy?” I asked her, hoping to catch her off guard. “What about the girl who killed herself? Were you treating her, too?”

The response was chilling. “What are you trying to imply?”

In for a penny, in for a pound. “I’m implying that you wanted them to kill themselves,” I said, buying precious seconds. “But you overplayed your hand with Kelley.”

She jerked her arm out of my grasp, sending me flying backward into the wall. I steadied myself and prepared for another blow.

It didn’t come.

“It’s a mercy, isn’t it?” I pressed. “What you offer them? What you do? What you did to Kelley.”

The footsteps were right upon us now, but I couldn’t afford to turn my back on the killer above me.

She leaned forward. “I had nothing to do with what happened to Kelley Peterson.”

I saw a flash of motion out of the corner of my eye. Lia rounded the corner, Michael beside her, gun in hand. He raised it.

“You with the righteously indignant, yet distinctly guilty expression on your face! Hands in the air!”

The psychologist’s gaze darted from me to Michael to Lia.

“Batman said to put your hands in the air,” Lia told her. “And while you’re at it, repeat what you just said about the death of Kelley Peterson.”