The story begins when Mrs. McGinty, an elderly widow, is found dead in her home. She had been murdered by a blow to the head, and the police quickly conclude that it was a botched robbery, with the killer trying to steal money from her. Mrs. McGinty’s home is modest, and the police suspect a local handyman named James who was known to have visited her before her death. However, the police have little evidence to link him directly to the crime, and he is soon arrested and convicted.

Despite the seemingly clear evidence, James insists he is innocent and appeals his conviction. His solicitor reaches out to Hercule Poirot, asking him to review the case, as there is something about the situation that doesn’t seem right. Poirot agrees to take on the case and investigates the circumstances surrounding Mrs. McGinty’s death.