Struggling single father Harvey Fowler finds a glimmer of hope when he crosses paths with Mandy Simpkins, the writer behind the beloved Marvelous Mandy children’s books that his daughter adores. Their lively and enchanting romance appears flawless, but things take a dark turn when Harvey uncovers unsettling truths about Mandy’s troubled mind. As her seemingly idyllic persona begins to unravel, Harvey discovers her true nature and the lengths she will go to preserve the facade of her ideal existence.