Nijemi svjedok

Emily suspects that someone has attempted to poison her after she falls down a flight of stairs, which she believes was a deliberate act. She writes a letter to Poirot asking for help, but sends it too late. She dies of natural causes, according to the medical certificate, and her fortune is inherited by her relatives. However, Poirot discovers that Emily has changed her will, leaving everything to her companion, Minnie Lawson, instead of her family.

Poirot begins his investigation, questioning Emily's relatives: the greedy Bella Tanios, her unhappy husband, and the charming but wasteful Charles and his sister Theresa. A key witness is Emily's dog, Bob, who, although "dumb", provides subtle clues. Poirot analyzes the motives and circumstances of each suspect, discovering that Emily was poisoned with phosphorus, which caused her death. Through conversation, observation, and logic, Poirot uncovers the killer...

The novel explores themes of greed, family conflict, and moral duplicity, as Poirot's genius and attention to detail lead to the solution. Bob, the dog, symbolizes loyalty and inadvertently helps uncover the truth.