When a county employee is found shot to death in sun-drenched daylight while sitting in his county road grader, Undersheriff Bill Gastner is faced with puzzling questions. The simplest explanation-that an errant bullet from a careless target shooter's rifle blew out Larry Zipoli's brains-is soon discarded as inconsistencies surface. The fatal bullet shows no rifling marks, and investigation reveals that the shooter walked directly toward the road grader, in full view of the victim-who did nothin