My husband Matt and I are an ordinary married couple in every way but one. At the end of each day, we return to our own homes and our own spaces. But beyond the fairy lights I string at my window, darkness is pressing in. Two local women have gone missing, and I don't want to be alone. Sipping our coffees, looking out of my kitchen window, I soon notice how observant Brenda is. When she tells me that perhaps my husband isn't simply working late, something cold takes root.

In 2010, Brooke Lowry, Carrie Hollis, and Eve Shay were inseparable. But on the Fourth of July, Eve vanished—her case never solved. Brooke moved away, but Carrie couldn’t let go, her obsession driving her to become the Chief of Police. Now, fifteen years later, just as Carrie is about to close Eve’s case for good, an anonymous call provides a chilling new lead. And–within days–a man’s body is hauled in by a fishing boat. His murder is linked to a hotel a few miles away–where the guest in the room next door was none other than Brooke Lowry.

When Emily Lane isn’t busy running her charming Christmas-themed store, “Under the Mistletoe”, located in the quaint tourist town of Fletcher’s Grove, she finds herself compelled to investigate not so quaint local murders. On the surface, Emily is a perfectly lovely, good-natured puzzle-solver and mystery lover. But she is hiding a secret past from everyone in town. And when Emily begins her personal investigations, Detective-Constable Sam Wilner, a smart and attractive cop—with a crush on Emily that is not completely unrequited—begins to wonder if there’s more to Emily than meets the eye.

Two high school teachers—Amber Dorris and Leticia Laye—become obsessed with a true-crime podcast about the 1999 murder of 12-year-old Sarah Gerlach. Amber’s marriage to her real estate agent husband Gary is on the rocks. As a distraction, she and Letitia become increasingly absorbed by the case against local Blake Wernerhet. Blake was convicted of murdering Sarah, who was the little sister of a friend of his. While he maintains his innocence, everything points to this man being a vicious killer of an innocent girl.

FBI agent Sarah Cole is stunned to receive an invitation to the “Game of Nines,” the most secretive and longest-running murder puzzle in history. Thrust into a mystery that has confounded law enforcement for decades, she proves to be an unexpectedly formidable "player"—and might finally end the deadly game once and for all.