When Clara receives an anonymous letter on her fortieth birthday, her carefully constructed life begins to unravel. "Who do you think you are?" the letter asks—a question that haunts her as she discovers her late mother's hidden past. Haunted by fragments of a childhood she barely remembers, Clara embarks on a journey from London's gleaming towers to a remote coastal village, where secrets about her origins have waited decades to surface. As she pieces together the truth, Clara must confront the woman she's become—and decide whether identity is something we inherit, or something we choose.