The Mystery of Hunter's Lodge

Hercule Poirot and Captain Hastings are visited by Roger Havering, the son of Baron Windsor. Havering is staying in London and has just received a telegram from his wife, Zoe, saying that his uncle, Harrington Pace, was murdered last night in Derbyshire. As Poirot is ill in bed, he agrees to Hastings investigating in his place. Hastings and Havering leave immediately, taking a train north.

That afternoon, they arrive at Hunter's Lodge, a small stone building in the Derbyshire moors, where the murder occurred. To Hastings' surprise, Inspector Japp is already at the scene, having been called from London. As Japp questions Havering, Hastings interviews the housekeeper, Mrs Middleton, who tells him she showed a black-bearded man into the house's gun room the previous evening to see Pace. She and Mrs Havering were outside the room where the two men were talking when they heard a shot. The door to the room was locked but they found an open window. Gaining entry, they discovered Pace dead, seemingly shot by one of a pair of revolvers which were on display in the room. The revolver and the black-bearded man are both now missing.

Mrs Middleton then sends Mrs Havering, who is resting upstairs, to see Hastings and she confirms the housekeeper's story. Japp, meanwhile, confirms Havering's alibi for his being in London. Soon the missing pistol is found dumped in Ealing, London. Hastings wires Poirot with the details, but Poirot is more interested in the clothes worn by and descriptions of Mrs Middleton and Mrs Havering. Poirot wires again saying to arrest Mrs Middleton, but she has disappeared and no trace of her can be found, either from the agency that sent her or regarding her means of reaching Derbyshire.

Once Hastings returns to London, Poirot presents his theory – Mrs Middleton never existed. She was Zoe Havering in disguise. Only Roger Havering claimed to have seen the two women together at the same time. Havering travelled to London with one of the revolvers, which he dumped, and Mrs Havering shot Pace with the other revolver. Japp is convinced of the theory but does not have enough evidence to make an arrest. The Haverings inherit their uncle's fortune but are killed soon after in an aeroplane crash.