Late one night, the residents of Styles wake to find Emily Inglethorp dying of what proves to be strychnine poisoning. Hastings, a houseguest, enlists the help of his friend Hercule Poirot, who is staying in the nearby village. On the day she was killed, Emily Inglethorp was overheard arguing with someone, most likely her husband, Alfred, or her stepson, John. Afterwards, she seemed quite distressed and, apparently, made a new will - which no one can find. She ate little at dinner and retired early to her room with her document case. The case was later forced open by someone and a document removed. Alfred Inglethorp left Styles earlier in the evening and stayed overnight in the nearby village, so was not present when the poisoning occurred. Nobody can explain how or when the strychnine was administered to Mrs. Inglethorp. The Mysterious Affair at Styles launched the career of Agatha Christie, and introduced one of the defining literary characters of the 20th Century.