While studying outside in broad daylight, a girl is decapitated with a chainsaw by an unidentified killer who steals her head. Lt. Bracken and his partner, Sgt. Holden, investigate the murder. The school's dean asks Professor Brown, who teaches anatomy, to give the detectives a tour of the school. Outside, the groundskeeper, Willard, is seen trimming a hedge with a chainsaw. In the library, a student named Kendall receives a note given by a girl to come to the pool later; the killer finds it and tracks down the girl at the pool, where she is brutally killed with the chainsaw. Willard later arrives on the scene and is arrested, believed to be a suspect. Near the pool, they find the chainsaw and the girl's body parts, save for her torso.