An unnamed man (Timothy Bottoms) (simply called "young man" in the credits) sneaks into Ocean View Amusement Park and places a small radio-controlled bomb on the tracks of the park's wooden roller coaster, The Rocket. The bomb detonates, a coaster train derails, killing and injuring the riders. Safety inspector Harry Calder (George Segal), who initially cleared the ride, is called to the park to investigate. A park worker tells Calder that he saw what he thought was a park maintenance man up on the tracks earlier that day but did not state that the man was someone other than the park had authorized to be there.