A strangely equivocal morphology of detective fiction that reads every one of its considerable range of forms as a recurrence of a single, rigidly conventional formula. The structuralist approach that Roth (English/Univ. of Minnesota) takes to his material has been around for 70 years and has in fact been the preferred approach to the genre for commentators as diverse as John Dickson Carr, Roland Barthes, Geoffrey Hartman, and Umberto Eco. What's new here is the inclusion of espionage writers like Ian Fleming together with Agatha Christie and Mickey Spillane, and the coolly neutral tone of Roth's assessments, as when he remarks that ``bad writing, rather than being a failure of the genre, is actually a characteristic of it, emerging from its center.'' Roth's method is topical rather than historical. Successive chapters consider the masochistically avid detective hero, the absent or bad-girl heroine, the improbably ingenious criminal, and the conventions of airtight solutions, physical clues, and impossible coincidences. But the formal detective novels of Christie and Dorothy Sayers dictate the pattern into which Roth squeezes the later hardboiled stories and spy thrillers. Roth's most original move--to read spy stories as detective stories--is his least convincing, and his readings of ``perverse'' detective conventions like the omnicompetent hero and the reliance on spurious logic are marred by his obvious impatience with the very categories he is using. Telltale slips (e.g., about the year of Hercule Poirot's debut) will make fans of the genre as dismissive of Roth as he is of them. The best things here are at the edges, whenever Roth places detective stories in the context of popular formulas that include boys' adventure stories, sensation novels, and science fiction. Detective stories, Roth concludes, are a form of cultural junk dedicated to examining the junk their culture would prefer to hide. His own ambivalence toward junk is what gives this analysis its perverse but limited appeal.