The 1978 Scottsdale, Arizona, murder of the star of the long- running TV sitcom Hogan's Heroes is reviewed in infinite detail here by Graysmith, who did the same job for a series of 70's and 80's rape-murders in San Francisco (The Sleeping Lady, 1990). In his opening chapters, leading up to Bob Crane's murder, Graysmith retells every date and sexual activity the star engaged in--whether or not they had anything to do with his death. Going by what we have here, much of Graysmith's superfine detail is superfluous as evidence, though it does render the victim's character. This density of fact, however, veils the weakness of the author's approach, which hangs upon circumstantial evidence and what after 14 years may become hard evidence by way of new forensic techniques in sampling DNA specimens and minute bits of blood and fatty brain tissue. Crane was living on reruns and a kind of supper-club-circuit play he was taking around the country when he befriended an overweight electronics salesman, John Carpenter, who consistently failed to score on double-dates with Crane even while Crane scored daily, if not twice daily, taking Polaroids and videos of his romps. Then the actor was found in bed with his head battered in by a blunt object. Scottsdale investigators finally linked Carpenter to the murder, but the state could find neither weapon, witness, nor motive and so failed to prosecute. But detectives refused to close the case, and Carpenter--who in the interim had entered a plea bargain in L.A. for molesting female minors--recently was arraigned for the killing. Gruesomely sexy but not a provocative read. (Eight pages of photos, 23 line drawings).