SOURCE: "Ordeal by Analysis: Agatha Christie's The Thirteen Problems," in Twentieth-Century Suspense: The Thriller Comes of Age, Macmillan, 1990, pp. 80-95.

In the following essay, Day discusses the structure of The Thirteen Problems, refuting many commonly held beliefs about the simplicity of the formulaic mystery novel.

Critics of the detective story have commented that its appeal lies less in characterization than in the solution of a problem. Jacques Barzun writes that 'detection rightly keeps character subordinate' while George Grella comments 'that the central puzzle provides the form's chief appeal'. Generally, characters are types who perform specific functions and only the detective is allowed to be interesting.

This description derives from a certain view of the detective story as formula, and considering it on that basis it is fairly sound. However, it does beg certain questions, the most obvious being whether the majority of readers are really motivated by the...