The heiress Linnet Ridgeway Doyle boards the cruise steamer Karnak with her new husband Simon. They are honeymooning in Egypt, but they realize they are being stalked by Linnet’s friend Jacqueline, an old rival for Simon’s affections. Several other people on the Karnak also have grudges against Linnet. After the failure of an initial attempt on her life during a day tour, Linnet is found dead in her stateroom. The murder weapon resembles a gun Jacqueline used to attack Simon the night before.
Also on board the Karnak is Belgian detective Hercule Poirot, the hero of many Christie novels who is famed for his ability to deduce the identity of a killer by observing tiny details. Poirot is soon joined by Col. Race, an old friend seeking a criminal he believes to be traveling aboard the Karnak. Race becomes Watson to Poirot’s Sherlock Holmes, aiding the detective and providing Poirot a reason to explain his methods.
Although Jacqueline seems the prime suspect, she has an alibi, forcing Poirot to focus on the other passengers. Novelist Salome Otterbourne is battling a libel lawsuit Linnet filed against her; she is traveling with her devoted daughter, Rosalie. Linnet’s lawyer, Andrew Pennington, who was embezzling from her, conveniently joined the cruise just before it sailed. American socialite Marie Van Schuyler is traveling on the Karnak with her cousin, Cornelia, and nurse Miss Bowers; the kleptomaniac Marie had her eye on Linnet’s jewels.
The mysterious Mr. Ferguson is a communist who resents the Doyles’ wealth on general principles. Archaeologist Signor Richetti hides a deadly secret. Austrian doctor Ludwig Bessner had bitterly debated politics and medicine with Linnet. Until they know the truth, Poirot and Race cannot eliminate anyone else on board, including Tim Allerton and his cousin, Joanna Southwood, or the quietly reserved James Fanthorp; they all turn out to be concealing secrets. Poirot soon discovers that even Linnet’s maid, Louise Bourget, had reason to resent her employer, as did an engineer on board named Fleetwood.
Louise discovers the killer’s identity but is murdered when she attempts blackmail. Another character also dies just before revealing the killer to the other passengers. Through the process of elimination and careful attention to detail, Poirot soon discovers the truth. To reveal that truth would spoil a mystery that still confounds readers in the 21st century. “Death on the Nile” became a graphic novel in 2003 and a computer game in 2007, reports agathachristie.com.