I had the perfect life with my devoted stay-at-home husband, great career, and beautiful daughter. Until my husband’s obsession with perfection took a dark turn and I learned more about my sister-in-law’s suspicious suicide.

I had only just gotten promoted to executive director at Morgan Stanley – one of the youngest ever – when I began to notice that something wasn’t right in our house.

The walls change shades overnight. Coffee cups appear in strange places, always full and cold. And my husband Mark’s obsession with perfection grows more disturbing by the day. An encounter with his schizophrenic father makes me question everything I thought I knew about their family. Mark’s father’s cryptic warnings about his daughter Rachel—whose supposed suicide a decade ago is shrouded in secrecy—suggest a darkness that goes beyond mental illness.

As I uncover the truth about Rachel’s death, Mark’s increasingly erratic behavior begins to terrify me. Like his father, Mark seems to be losing his grip on reality—but I suspect something far more sinister than mental illness is at play when it comes to Mark. And that it’s the reason Rachel is dead.

But before I can do something about it, it’s too late…