悬崖上的谋杀 (1934)

Why Didn't They Ask Evans? is a mystery novel by Agatha Christie, first published in the United Kingdom by the Collins Crime Club in September 1934 and in the United States by Dodd, Mead and Company in 1935 under the title of The Boomerang Clue. The UK edition retailed at seven shillings and sixpence (7/6) and the US edition at $2.00.

The novel is set in Wales and Hampshire. Bobby Jones finds a man dying at his local golf course. A photo he saw in the man's pocket is replaced, as police seek his identity. Bobby and his friend Lady Frances Derwent have adventures as they solve the mystery of the man's last words: "Why didn't they ask Evans?"

The novel was praised at first publication as "a story that tickles and tantalises", and that the reader is sure to like the amateur detectives and forgive the absence of Poirot. It had a lively narrative, full of action, with two amateur detectives who "blend charm and irresponsibility with shrewdness and good luck". Robert Barnard, writing in 1990, called it "Lively" but compared it to Evelyn Waugh's Vile Bodies and felt that the detectives were too much the amateurs.

Plot

Bobby Jones is playing golf with Dr Thomas in the Welsh seaside town of Marchbolt. Upon hearing what sounds like a scream, he peers over the edge of the cliff and sees a man lying on the rocks below. Bobby climbs down to the man, then calls up to the doctor to go for help. He stays with the dying man, who briefly regains consciousness and says "Why didn't they ask Evans?,” before he dies.

Bobby finds a photograph of a beautiful woman in the man's coat pocket, but nothing to identify the man himself. Bobby is needed at his father's church to play the organ, so another man, Roger Bassington-ffrench, a stranger who is wearing plus fours, offers to stay with the body.

At the inquest into the death, the man’s sister, Amelia Cayman, identifies him as Alex Pritchard. She is said to be the woman in the photograph (though Bobby wonders how such a beautiful girl could become such a coarse older woman). After the inquest, Mrs. Cayman and her husband ask if Pritchard had any last words. Bobby says no somewhat hesitantly but later, when talking with his friend Lady Frances "Frankie" Derwent, Bobby remembers Pritchard's final words and writes to the Caymans to tell them.

Bobby receives and rejects an unexpected job offer from a firm in Buenos Aires. Soon afterward he nearly dies after drinking from a poisoned bottle of beer. The local police do not investigate this incident, but Frankie thinks someone has tried to murder Bobby.

When Bobby sees the issue of the local paper with the photograph used to find Pritchard's sister, he sees that it is not the one he found in the dead man's pocket. He and Frankie realise that Bassington-ffrench swapped the photographs and that Mrs Cayman is not related to the dead man. Bobby and Frankie trace Bassington-ffrench to Merroway Court in Hampshire, owned by Roger's brother and sister-in-law, Henry and Sylvia. They stage a car accident outside the house with the help of a doctor friend so that Frankie, feigning injury, will be invited to stay to recover. Frankie produces a newspaper cutting about the mysterious dead man; Sylvia remarks that he looks like Alan Carstairs, a traveller and big-game hunter who was a friend of John Savage, a millionaire who killed himself after learning he had terminal cancer.

Frankie meets two neighbours of the Bassington-ffrenches – Dr Nicholson, who runs a local sanatorium, and his younger wife, Moira. Investigating in the grounds at night, Bobby encounters a woman who says that she fears for her life; she is the woman whose photograph Bobby found in the dead man's pocket. Several days later, Moira Nicholson turns up at the local inn where Bobby stays in his disguise as Frankie's chauffeur. She says her husband is trying to kill her and says she knew Alan Carstairs before her marriage to the doctor. Moira suggests that Bobby and Frankie ask Roger if he took the photograph from the body of the dead man. Roger admits that he took the photo, recognising Moira and wanting to avoid scandal for her. Frankie leaves after Henry Bassington-ffrench is found dead in his home, an apparent suicide.

Interested in the will of the late John Savage, Frankie consults her family's solicitor in London and learns that Carstairs had consulted him too. Savage was staying with Mr and Mrs Templeton when he became convinced he had cancer, although one specialist told him he was perfectly well. When he died by suicide, he left in his will some donations to charity and seven hundred thousand pounds to Mrs Templeton, who has apparently since left Britain. The will was signed by two witnesses - the cook and the gardener of the Templeton's residence - as well as the lawyer, so there was no doubt about its correctness; Carstairs was on their trail when he was killed. Bobby is kidnapped while checking and lurking at the Grange; Frankie is lured to the same isolated cottage by Roger disguised as Dr. Nicholson, where she is captured and tied up with Bobby in the attic. Bobby and Frankie are rescued by the timely and unexpected arrival of Badger Beadon, and they turn the tables on Roger; they also find a drugged Moira in the house. When the police arrive, Roger has escaped.

Bobby and Frankie trace the Templetons' former cook and gardener, witnesses to John Savage's will. Mr Templeton is also known as Mr Leo Cayman. The cook says that Gladys, the parlourmaid, was not asked to witness the will, made the night before Savage died. Frankie realises that the cook and gardener did not see Mr Savage before the signing, while the parlourmaid did and would have realised that it was Roger in the "deathbed" who wrote the will and not Mr Savage. The parlourmaid is Gladys Evans, hence the reason for Carstairs' question, "Why didn't they ask Evans?"