A wealthy patriarch is murdered in his locked room on Christmas Eve, forcing Hercule Poirot to untangle a web of family secrets and long-standing resentments. The detective arrives at the Gorston Hall estate to find the victim, Simeon Lee, dead in a pool of blood, with his estranged children and their spouses gathered for the holiday. Poirot must navigate the complex dynamics of a dysfunctional family where every member possesses a motive and a hidden agenda. The narrative utilizes a classic third-person perspective, focusing on the psychological interplay between the suspects and the methodical gathering of clues by the detective.

This novel is widely regarded as a quintessential example of the Golden Age of detective fiction, praised for its intricate plotting and clever subversion of holiday tropes. Readers often highlight the satisfying resolution and the sharp characterization of the Lee family members as standout elements of the narrative. The book maintains a reputation for being a tightly constructed puzzle that challenges the reader to identify the killer among a crowded field of suspects. Its enduring popularity stems from the effective blend of domestic tension and the precise, analytical approach of the protagonist.