Likable cop vs. psycho-killer in Beverly Hills--as Westbrook (The Magic Garden of Stanley Sweetheart) offers a competent, brightly peopled, yet thoroughly predictable variation on a formula that's been given far more compelling treatment in recent years by the likes of Thomas Harris (Red Dragon) and Herbert Lieberman (Nightbloom). The psycho, only half-believable in his homicidal frenzy, is Lawrence Ferguson, 47, a homely, repressed, unmarried office worker: diagnosed as terminally ill with cancer, Lawrence supposedly goes off his rocker--and quickly becomes the notorious ""Car Killer,"" shooting wealthy strangers (the sort of people he has always envied) as they drive around Beverly Hills in their fancy cars. Meanwhile, in alternating chapters, we follow the investigation of the Car Killer case by wry, handsome cop Nicky Rachmaninoff--whose private life includes a famous ex-wife (Susan Merril, star of TV's ""Cassie and the Cop""), weekend fatherhood, memories of a beloved cop-father, and a steamy/serious new affair with the widow of the one of the Car Killer victims. Tough, individualistic Nicky has the usual mn-ins with the police establishment as he follows hunches and leads that his colleagues pooh-pooh. After he's been taken off the case, he suddenly zeroes in on the identity of the Car Killer (largely through a contrived bit of very good luck). And the all-action, all-clichÃ‰ finale features Nicky in roaring pursuit of psycho Lawrence--who has kidnapped Susan Merril and fled to a hideaway in the desert. (Yes, as in so many similar thrillers, the psycho-killer just happens to be erotically obsessed with the hero-cop's wife, lover, or ex-wife.) Unoriginal, too, are many of the character touches along the way: Nicky, for instance, is a workalcoholic who must be forced--by his new love--to feel and cry. But, if thoroughly derivative and devoid of genuine suspense, this is a solid, highly readable imitation of the real thing--with slick narration, ironic dialogue, and an efficient sprinkling throughout of Beverly Hills glamour, Hollywood decadence, and offbeat charm.