The story of the woman who murders her husband with a frozen leg of lamb and then has the murder weapon eaten by the detectives is one of the most famous examples of the “perfect crime” story. However, this work’s value lies, not simply in the originality of the murder method but in the way that Roald Dahl ties this to larger themes. The use of a leg of lamb as an instrument of death reveals the hidden and sinister meanings that lie in seemingly innocent objects. Dahl, like many modern suspense writers, weaves his stories around trivial, everyday events that suddenly take on frightening aspects revealing the danger and uncertainty that underlies modern life, rather than reviving medieval settings and horrors in the manner of the earlier gothic writers.
Mary Maloney lives the life of a devoted housewife almost until she actually murders her husband. The news of her divorce causes no outward change in her behavior. She goes on, as if pretending that nothing has happened will make it so. The murder seems almost an unconscious and unwilled act. However, after the murder, Mary becomes a deliberate and clear thinker. She now artificially creates her alibi for the murder by consciously returning to her innocent state before Patrick’s death. She practices her lines, voice tone, and facial expressions before she goes to the grocery so that they will appear perfectly natural and arouse no suspicions in the grocer’s mind. When Mary arrives home, her shock at seeing Patrick’s body is so spontaneous that she almost seems to have fooled herself. Mary’s deception grows as she manipulates the police, reaching its peak when Patrick’s friends destroy the evidence of his murder as a favor to his wife, who is his killer.
Dahl creates a series of bizarre metamorphoses in this story. A leg of lamb becomes a murder weapon. Mary Maloney, the victim of her husband’s insensitivity, makes him her victim. Patrick, an investigator of crimes, becomes the subject of a criminal investigation. A dead man’s friends console his murderer. The police destroy the evidence needed to trap the criminal. The best hiding place for the murder weapon turns out to be right under the officers’ noses. Dahl reveals how much of “normal” existence is actually a contrived appearance that can be easily manipulated. Mary moves outside the predictable by turning the lamb into a weapon, then overcomes the police by turning the weapon back into a lamb. Having experienced what lies beneath the surface, she can now arrange appearances to her own advantage.