Agatha Christie: The Imposter Mystery
May 4 2021
Agatha Christie was probably the most popular mystery writer of all time, and it is interesting to study her stories for that reason.
Almost all of Agatha Christie’s stories revolve around imposters, people who turn out not to be who they claim to be. We have innocent young girls who turn out to be experienced jewel thieves, we have maids who turn out to the be the accomplices of murderers, we have brother and sister pairs who turn out to be nothing of the kind, we have the adopted son who turns out to be the child, assumed to be female, of an infamous murderer, we have a young mother who turns out to be a ruthless Nazi agent, who has kidnapped an infant so that she can pose as a mother. Even in her famous play The Mousetrap the villain is a murderer posing as a police officer.
Often the solution to a Christie mystery hinges on the detective uncovering the true identity of one of the other characters, or their true relationship to the victim. While other writers do use this plot device, Christie uses it almost consistently.
For example in “Evil Under The Sun” a husband and wife, both assuming false identities, work together to swindle and murder wealthy women in such a way that the husband, who commits the murders, will seem to have an unassailable alibi. Their technique is to shift the apparent time of the murder to an earlier hour, when the husband has an alibi. The husband then meets his victim, and kills her in safety, because her death has already been reported.
In their first murder the wife, posing as a cyclist on a holiday tour, under an assumed name, raises the alarm, reporting to the police that she has found the body of a murdered woman at a time when her husband is safely travelling on a train, with multiple witnesses to his itinerary. By the time the wife leads the police back to the spot where she claims to have found the body, there really is a body.
The husband has arranged to meet his victim at the spot, and kills her while his wife is talking to the police. The time she claims to have found the body at a time earlier than the actual murder, but not enough to conflict seriously with the police surgeon’s assessment of time of death. As the fiance of the murdered woman, who would inherit her considerable estate, the husband was naturally suspected, but his alibi was perfect, and the police have no idea that their lady cyclist was actually his real wife.
In their second murder, the actual murder of the story, the husband has convinced a wealthy woman to invest in a fraudulent scheme that will give him her entire fortune. He then kills her, with the help of his wife, to prevent his fraud from coming to light.
The wife poses as the victim, sunbathing under a hat on the beach. The husband, with a witness in toe, pretends to find the victim dead of strangulation, and sends his witness off to get help while he stays with the “body”. In the meanwhile the wife leaves the scene, and the husband meets the real victim and kills her. When help arrives they find the victim strangled as expected, and already reported. It seems impossible that the husband could have committed the murder. After all he had found the victim already dead, in the presence of a witness.
Sometimes Christie’s use of the imposter seems a bit of cheat, reminiscent of the once well known butler of the Edwardian stage who murders his employer because is he is actually a long-lost cousin who stands to inherit the estate. For example, in Christie’s Sad Cypress a young girl who has inherited a fortune is murdered by the district nurse, who turns out to be the victim’s aunt from New Zealand, who she has not seen for years, and who is the victim’s only heir. . Butler, District nurse, what’s the difference?
In principle the reader of a mystery is supposed to be able to guess the identity of the culprit from the clues laid down by the writer, but in the case of most of Agatha Christie’s stories this is very difficult because you rarely know who all the characters actually are and what their true relationship is. All you can generally be sure of is that one or more of the characters will be someone very different from who they seem to be, but beyond this you are at a loss.
This is not to say that other mystery writers do not use the imposter -- Dorothy Sayers’s Have His Carcase has two or three -- but few I imagine use it so consistently as Agatha Christie.
