Linnet Rideway is a young woman who has it all: wealth and beauty. Her best friend Jackie is penniless, but when it comes to beauty she is Linnet's equal. When Jackie brings her handsome fiancee Simon Doyle to visit Linnet and asks her to give him a job, the love story changes and Simon ends up marrying Linnet. The newlywed couple embarks on a idyllic cruise of the Nile that turns out to be deadly: Linnet is found murdered. Hercule Poirot, who happens to be aboard the Karnak, investigates her murder and those that follow.