Nina Garrity never got to confront her husband, Glen, about his affair or any of his other misdeeds, as he presumably drowned while fishing on his boat. A year and a half after the accident, Nina considers herself a widow, even though the police never found a body. Following a chance encounter with Simon Fitch, a teacher from her daughter Maggie's middle school, Nina finds love again. Simon, a widower still grieving the suicide of his first wife, has found his dream girl in Nina. Nina's teenage son, Connor, embraces Simon as the father he wishes his dad could have been, but Maggie sees a far darker side to this new man in their lives. Even Nina’s good friends wonder if Simon is supremely devoted --- or dangerously possessive.

Fifteen-year-old Meghan has been in and out of hospitals with a plague of unexplained illnesses. But when the ailments take a sharp turn, clashing medical opinions begin to raise questions about the puzzling nature of her illness. Doctors suspect Munchausen syndrome by proxy, a rare behavioral disorder where the primary caretaker seeks medical help for made-up symptoms of a child. Is this what's going on? Or is there something even more sinister at hand? Meghan's mother, Becky, must race against time to prove that her daughter has a deadly disease. But she first must confront her darkest fears and family secrets that threaten not only to upend her once-ordered life, but to destroy it.