Arson-sleuthing in Chicago--with crackling cop/fireman rivalry, trips through the arsonist's mind, and a surprising (if not entirely convincing) twist at the end. Cultured, divorced Fire Chief Rob Hammond, renowned arson-expert, reluctantly agrees to head Chicago's new task-force on arson. His abrasive new partner: Lieut. Dom Benedetto, a ""Neanderthal"" who sourly has to take second place in the investigation of a warehouse torching. . . till a cave-in lands Hammond in the hospital with assorted breakages. Meanwhile, Gettel introduces us to: the fat entrepreneur who has been arranging for the burning of his secretly-owned, over-insured buildings (an unidentified city official is under his thumb); and the hired fire-bug himself--a psycho who's now planning a diabolical super-fire. . . and personal vengeance on fire-investigator Hammond. (Hammond's girlfriend is murdered.) But though there's no mystery about the arsonists, there is that lingering puzzle concerning the city official who's in cahoots with the shady entrepreneur. And after a rather overwritten firestorm finale (multiple torchings and the capture of the firebug), there's that tricky twist, with a nicely ambiguous fadeout. Despite some excesses in Gettel's jumpy, streetwise style, then: a talented debut--strong on texture (Chicago dialogue, arson technology), enhanced by the dual-hero setup, and not nearly as predictable as it seems to be at first.