The search for a serial killer leads a woman into the twisted tangle of her own family tree in a chilling novel by the #1 Amazon Charts bestselling author of The Missing Sister and Lies We Bury . Adopted when she was only days old, Ivy Hon knows little about her lineage. But when she's stricken with a mystery illness, the results of a genetic test to identify the cause attract the FBI. According to Ivy's DNA, she's related to the Full Moon Killer, who has terrorized the Pacific Northwest for decades. Ivy is the FBI's hope to stop the enigmatic predator from killing again. When an online search connects Ivy with her younger cousin, she heads to rural Rock Island, Washington, to meet the woman. Motivated by a secret desire to unmask a murderous relative, Ivy reaches out to what's left of a family of strangers. Discovering her mother's tragic fate and her father's disappearance is just the beginning. As Ivy ventures into a serial killer's home territory, she realizes that she may be the next victim of poisonous blood ties.