The Pledge: Requiem for the Detective Novel

The Pledge (German: Das Versprechen) is a crime novella by Swiss author Friedrich Dürrenmatt, published in 1958, after Dürrenmatt thought that his previous movie script, Es geschah am hellichten Tag ("It happened in broad daylight") did not have a realistic ending. That made-for-television story had demanded an ending in line with that of a typical detective story. Dürrenmatt, however, was a critic of that genre of literature, and thus he set out to write Das Versprechen as an expression of that criticism. Although it has been absent from some subsequent editions of the novella, the title of the original edition included the telling subtitle Requiem for the Detective Novel (German: Requiem auf den Kriminalroman).

Dürrenmatt uses a first-person narrative to insert himself into a frame story as a writer of detective fiction. However, the primary narrator is actually a character named Dr. H., a retired police chief who takes on the role of explaining to Dürrenmatt's first-person character the flaws of the detective literature genre. To do so, Dr. H. relates the story of one of his former inspectors, Matthäi, who on his last day with the department, found himself called into an investigation of child murder. A suspect soon confessed to the crime, but knowing that the confession came only after the man was browbeaten in a relentless, 20-hour interrogation, Matthäi's keen police instincts told him that the man was not the real murderer. Matthäi felt that there was a serial killer at work, with the girl's murder being related to other child murders that had occurred in the area. However, he was alone in that assessment and the police closed the case.

Having made a solemn promise to the parents of the murdered girl that he would find the culprit, Matthäi abandoned the plans he had made for his life in retirement and instead continued investigating the case as a private citizen. He was warned by a psychiatrist that the murderer he sought likely did not exist and thus he might drive himself mad with his obsession in finding the man. Matthäi, however, was undeterred.

Through shrewd detective work, and driven by a growing and near maniacal obsession with the case, Matthäi was able to construct a detailed profile of the likely killer, down to the very road the murderer would probably travel to and from his evil deeds. Matthäi purchased a gas station along the route and then hired a housekeeper with a daughter named Annemarie, who matched the profile of the murdered girls. With Annemarie in place, living along the road as bait for the killer, Matthäi waited for the villain to come to him.

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