"The Last Thing He Told Me" is a novel by Laura Dave that follows the story of Hannah Hall, a woman whose husband, Owen, mysteriously disappears. As she grapples with his absence, she discovers a note he left her, urging her to protect his daughter, Bailey. This revelation leads Hannah on a quest to uncover the truth behind Owen's disappearance. Throughout the narrative, Hannah and Bailey navigate their complex relationship while unraveling secrets that challenge their understanding of Owen. The story explores themes of trust, love, and the lengths one will go to for family, all set against a backdrop of suspense and intrigue.