Rebecca opens with the narrator describing a dream of Manderley and then taking a long walk down memory lane. It covers her speedy courtship and marriage to Maxim de Winter and also shows us the initial phase of her new life at Manderley. The act closes with Mrs. de Winter going to bed after a disastrous costume ball.
The second act opens the very next morning, with Mrs. de Winter thinking her marriage is over. At the climactic moment, she is almost convinced by Mrs. Danvers to jump to her death from Rebecca's window. Shortly after, Rebecca's boat is found with her dead body inside, Maxim confesses to her murder, and Maxim and Mrs. de Winter rekindle their passion. Whew – what an act.
In the final act, we learn that Rebecca was terminally ill with cancer when she was killed; this gets Maxim off the hook, but makes us think that Rebecca instigated her own murder. The book closes as a happy Maxim and Mrs. de Winter drive toward Manderley, only to see their beautiful property ablaze in flames.