4x4

Catherine and Warrick investigate the death of a model who works at auto conventions after she is found murdered on a camper display. Nick looks into the death of a boy found beaten and burned to death on a bus bench near a strip mall. Elsewhere, a car accident leads Grissom to suspect that the driver intentionally hit his victim, while Greg and Sara examine the death of a body builder who died when a toxic mold ate him alive from the inside out.