A few of the more famous names jumped out right away: Susan Smith, who had drowned both her sons in 1994; Andrea Yates, who killed all five of her children after several years of struggling with psychosis and profound postpartum depression.

The list went on and on. None of these female perpetrators could be considered the victims in their cases, but the dominance of severe mental-health issues was clear.

Smith and Yates were both diagnosed with personality and clinical disorders. It was easy to imagine the same could be true of Mary Wagner, but a reliable diagnosis would take more time than we were likely to have together.

That particular question was sidelined a few hours into my research.

I clicked onto a new page and, sadly, found exactly what I was looking for.

A triple homicide in Derby Line, Vermont, on August 2, 1983. All three victims were siblings:

Beaulac, Brendan, 8

Beaulac, Ashley, 5

Constantine, Adam, 11 months.

The killer, their mother, was a twenty-six-year-old woman, with the last name Constantine.

First name, Mary.

I cross-referenced the homicide report for local media coverage.

It brought me to an article from a 1983 Caledonian-Record in St. Johnsbury, Vermont.

There was also a grainy black-and-white trial photo of Mary Constantine, seated at a defendant’s table.

Her face was thinner and younger, but the detached, stony expression was unmistakable, that look she had when she didn’t want to feel something, or had felt too much. Jesus.

The woman I knew as Mary Wagner had killed her own children more than twenty years ago, and as far as she was concerned, it had never happened.

I pushed back my chair and took a deep breath.

Here I was, finally, at the center of the labyrinth. Now it was time to start finding my way back out.

Chapter 107

Chapter 107

“NINETEEN EIGHTY-THREE, HUH? Jeez, that’s not even this century. All right, hang on a second. I’ll try to help you out. If I can.”

I sat through several minutes of tapping keys and riffling paper on the other end of the phone line.

The tapper and riffler was an agent named Barry Medlar, of the Bureau’s Albany field office. He was the coordinator of Albany’s Crimes Against Children Unit. Every FBI office has a CAC unit, and Albany has oversight for Vermont. I wanted to get as close to the source as I possibly could.

“Here we go,” Medlar said. “Hold on, here she is. . . .

“Constantine, Mary. Triple homicide on August second, arrested on the tenth. Let me scroll the rest of this. Okay, here we go. Sentenced NGRI on February first of the following year, with a state-appointed attorney.”

“Not guilty by reason of insanity,” I muttered.

So she hadn’t been able to afford her own defense; no legal bells and whistles on her behalf. Not guilty by reason of insanity can be a tough plea to prove. It must have been a fairly clear-cut case for it to go that way.