Joss and Phil's already rocky marriage is fragmented when Phil is injured in a devastating fire and diagnosed with Capgras delusion—a misidentification syndrome in which a person becomes convinced that a loved one has been replaced by an identical imposter. Faced with a husband who no longer recognizes her, Joss struggles to find motivation to save their marriage, even as family secrets start to emerge that challenge everything she thought she knew. With two young daughters, a looming book deadline, and an attractive but complicated distraction named Adam complicating her situation even further, Joss has to decide what she wants for her family—and what family even means.