No, the book ‘Atonement’ by Ian McEwan is not based on a true story. It is a work of fiction. The novel, published in 2001, tells the story of a young girl named Briony Tallis who falsely accuses her sister’s lover of a crime, leading to devastating consequences. The narrative explores themes of guilt, forgiveness, and the impact of misunderstandings. While the story is set against the backdrop of World War II, the characters and events are entirely fictional. McEwan’s skillful storytelling and vivid descriptions make the novel feel realistic, but it is not inspired by true events.