In a split second, Morgan Kincaid's life changes forever. She's on her way home from work when a mother begs her to take her baby, then places the infant in her arms. Before Morgan can stop her, the distraught mother jumps in front of an oncoming train. Morgan has never seen this woman before, and she can't understand what would cause a person to give away her child and take her own life. She also can't understand how this woman knew her name. The police take Morgan in for questioning. She soon learns that the woman who jumped was Nicole Markham, prominent CEO of the athletic brand, Breathe. She also learns that no witness can corroborate her version of events, which means she's just become a murder suspect. To prove her innocence, Morgan frantically retraces the last days of Nicole's life. Was Nicole a new mother struggling with paranoia or was she in danger? When strange things start happening to Morgan, she suddenly realizes she might be in danger, too.