When retired math teacher Grace Winters is left a run-down house on a Mediterranean island by a long-lost friend, curiosity gets the better of her. She arrives in Ibiza with a one-way ticket, no guidebook and no plan. Among the rugged hills and golden beaches of the island, Grace searches for answers about her friend's life, and how it ended. What she uncovers is stranger than she could have dreamed. But to dive into this impossible truth, Grace must first come to terms with her past.