In the war-torn London of 1939, 14-year-old Hazel and five-year-old Flora are evacuated to a rural village to escape the horrors of the Second World War. Hazel distracts her young sister with a fairy tale about a magical land, a secret place they can escape to that is all their own. When Flora suddenly vanishes while playing near the banks of the river, Hazel blames herself, and she carries that guilt into adulthood. Twenty years later, Hazel lives in an elegantly timeworn Bloomsbury flat with her charming boyfriend. But her tidy life is turned upside down when she unwraps a package containing an illustrated book called Whisperwood and the River of Stars. Could this book hold the secrets to Flora’s disappearance? Could it be a sign that her beloved sister is still alive?