The film is adapted from a phenomenal novel that has sold well around the world. Lily Bloom (Blake Lively) meets Lyle Kincaid (Justin Baldoni), a handsome and wealthy neurosurgeon. They fall in love at first sight and are addicted to each other. The perfect match of soul and body makes them quickly enter into marriage. However, why does Lily, who loves Lyle so much, choose to leave? What exactly broke their happiness?