When a deep-rooted memory suddenly surfaces, Elizabeth Burns becomes obsessed with the long-ago disappearance of her childhood friend April Cassidy. Driven to investigate, Elizabeth discovers a thirty-five-year-old newspaper article revealing the details that had been hidden from her as a child: April's mother, Adele, drove with her two young daughters deep into the woods where she killed first them and then herself.

Elizabeth, now a mother herself, tracks down everyone—Adele Cassidy's neighbor, her psychiatrist, her sister—who might give her the insight necessary to understand how a mother could commit such a monstrous crime.

Elizabeth's investigation leads her back to herself: her compromised marriage, her demanding children, her increasing self-doubt, her desire for more out of her own life, and finally to a fearsome reckoning with what it means to be a mother and wife.