It seems as if two out of every three suspense novels in recent years have featured psychopathic mass murderers--but Harris' contribution to the genre stands well above the pulpy crowd. Unlike Lawrence Sanders et al., Harris (Black Sunday) isn't in the vulgar titillation business; his territory is evil, not just violence--and, with unpretentious echoes of William Golding's Darkness Visible, he has written a genuinely frightening but completely un-lurid novel. . . featuring the most quietly convincing psychopath in recent American thriller fiction. The crimes are truly horrible: two whole families in far-apart suburban towns have been slaughtered one month apart--by, medical evidence shows (blood, hair, saliva), the same man. So supremely intuitive FBI-man Will Graham very reluctantly comes out of retirement (he killed someone and was himself nearly killed in recent cases), and while Graham's grim, shrewdly detailed investigation clicks along, Harris introduces us to the killer: Francis Dolarhyde of Gateway Film Laboratory in St. Louis. Facially deformed at birth, abused and abandoned as a child, Dolarhyde--now near-normal-looking thanks to plastic surgery--is a pathetic, sexually repressed, believably motivated madman: like ""Son of Sam,"" he is driven by a demonic voice, a voice he has come to associate with a Blake watercolor that joins sex and evil in the image of a red dragon. But Harris never lays the psychopathology on too thick; the pacing remains acutely taut as Dolarhyde (who selects his victim families from the home movies he processes) plans a third monthly killing. . . but is slowly drawn out into the open by the national publicity the murders are getting. (Graham is forced to cooperate with a National Enquirer-like reporter--who becomes a doomed decoy and dies grotesquely.) And Harris even manages to make something painfully, affectingly plausible out of the oldest horror-story cliche: the monster falls in love--with a blind colleague; and his struggle not to kill her (despite orders from his voices) culminates in a marvelous scene as Dolarhyde charms his way into the Brooklyn Museum and eats that Blake watercolor. Only the novel's final twist (after Graham has tracked Dolarhyde down and witnessed his demise) is too slickly predictable; only the portrayal of Graham's worries over his own capacity for evil seems strained (with some corny lapses into Bogart-ish dialogue). Everywhere else, this is a canny yet uncontrived mixture of deduction, suspense, action, and horror--far better written than most thrillers (Harris is sometimes a fine, lean, ironic stylist), with spine-chills all the way. . . and a fundamental decency and intelligence you won't often find in this usually exploitational genre.