A nameless young terrorist threatens to sabotage roller coasters at various American amusement parks if he isn't paid a huge ransom. Safety inspector Harry Calder is reluctantly drawn into a game of cat and mouse, with many lives at risk.
When a roller coaster in California goes off its track, killing several people, safety inspector Harry Calder, who had recently inspected the coaster, is assigned to investigate. After another amusement park suffers a suspicious fire, Calder uncovers a blackmail plot by a psychopathic terrorist. The terrorist seems to know everything Calder and the FBI say and do, and insists that Calder deliver the blackmail money personally at an amusement park in Virginia. After running Calder all over the park, the money drop is made and the terrorist gets away, but he discovers that the FBI had marked the money, making it useless to him. He plots to get revenge by blowing up a giant new roller coaster on its opening day, and it's up to Calder to stop him.—Mark Walker
The plot is about a guile young terrorist who is able to blackmail a series of companies by placing home-made radio controlled bombs within the central attraction of amusement parks; roller coasters. The young man played by Timothy Bottoms gives a hard time to the cops after they give him UV marked money. He then wants revenge and places a bomb in a roller coaster at the most important amusement park event of the year.—Nebiros <[email protected]>
In a series of amusement parks, something deadly is happening. Rollercoasters are flying off their tracks, and people are dying. It soon becomes apparent that these are not a series of coincidences, but the work of a psychopathic extortionist who is placing explosives on the tracks. The FBI is called in to investigate and traces the crimes to a young man. But even after the man gets his ransom, he plans to blow up another rollercoaster...this one at a well-known park in California. Will the FBI be able to arrest him before he can carry out his murderous plan...or will another rollercoaster go off the rails?—Derek O'Cain
Several severe accidents happen in different amusement parks. Technical supervisor Calder suspects it's no coincidence and starts to investigate. Soon he finds out that a psychopath blackmails a whole conglomerate of companies for a million dollars, and urges them to inform the FBI. But the blackmailer, who observed the company bosses all the time, learns about it and demands that Calder delivers the money... and sends him on a nerve-shattering trip through an amusement park to deliver the money, while the FBI observes him closely and tries to bust the electronically skilled terrorist.—Tom Zoerner <[email protected]>
A young, unknown man (Timothy Bottoms) enters an amusement park (we see a sign identifying it as the Ocean View Amusement Park, but in the film's story it is implied that the park is somewhere near the coast of California) and lays a small bomb onto the tracks of the Rocket, the park's wooden roller coaster. The man uses a radio control to detonate the bomb, which causes the roller coaster's train to derail, resulting in the death of 24 people riding on the train and injuries to several other riders. The ride's safety inspector, Harry Calder (George Segal), who had cleared the ride only hours earlier, is called to the park to investigate the incident. One of the park workers tells Calder that he saw someone that he believed to be a park maintenance man up on the tracks earlier in the day, although he doesn't state that the man was someone other than the man that the park had authorized to be there.
The young man who had placed the bomb on the Rocket's track then enters the Wonderworld amusement park in Pittsburgh, where the bomber starts a fire in the park's dark ride. When Calder learns about the Pittsburgh park's fire, he thinks that it may be linked to the bombing of the Rocket. After Calder learns that several executives of the companies that run America's largest amusement parks are having a meeting in Chicago, he flies there and goes to the Hyatt Regency hotel to intrude on the meeting. One of the executives plays back a cassette tape recorded by the bomber, where he tells the executives that he will only stop his activities when they agree to his demand for one million dollars.
Back at his home, Calder is visited by FBI agent Hoyt (Richard Widmark), who tells Calder to deliver the bomber his extortion money at the King's Dominion amusement park. At the park, Calder is instructed to wait at a telephone near the park's carousel. The bomber calls Calder and informs him that there is a bomb inside the park. The bomber sends a two-way radio to Calder so that the two can keep in contact, then orders Calder to go on many of the park's rides, including the Vertigo, the Wave Swinger, the Shenandoah Log Company flume ride, Lion Country Safari monorail, Rebel Yell, Apple Turnover and Sky Rail, where the bomber tells Calder that the bomb is in the two-way radio and warns him not to throw the radio away otherwise it will explode after it hits the paths below the gondolas, on which many of the park's visitors are walking. The bomber's next order to Calder is to falsely signal that the money has been dropped off as a way of diverting the FBI from finding him, then leave the suitcase containing the money on a park bench near the Space Copters. Calder complies with the bomber's demands, then walks away from the bench. Later, Hoyt tells Calder that he marked the money, despite this being in violation of the demands of the bomber. Calder leaves the two-way radio with the bomb squad as he demands to be taken home.
After Calder returns home, he receives another phone call from the bomber, who blames Calder for marking the extorted money and threatens to attack another park. Working on the assumption that the next attack will be directed at him personally, Calder deduces that the next target will be a brand new roller coaster known as The Great American Revolution that will be opening soon at Magic Mountain in Valencia, California. He shares his suspicions with the FBI, who initially reject Calder's hypothesis, but when they find out that the roller coaster is scheduled to open on Independence Day (July 4), the season peak of the amusement park's attendance, they decide to investigate anyway.
When the day of The Great American Revolution's opening arrives, the amusement park stage an opening concert at which pop group Sparks perform. A number of FBI agents arrive at the park disguised as maintenance men, and after some searching, some of them find a bomb tied to the roller coaster's track and disarm it. With The Great American Revolution just moments away from opening, the bomber returns to his car and retrieves another bomb. After he conceals it, he finds a park guest who has a Gold Ticket, which entitles the ticket holder to be one of the passengers on The Great American Revolution's first ride, and pays them $100 to buy it. After the bomber takes a seat in the rear of the train, he plants his new bomb beneath the seat. After the first ride finishes, the bomber gives an exit interview to a reporter, and while he is doing so, Calder recognizes his voice. He pursues the bomber and alerts the other FBI agents that he may have placed something suspicious on board the roller coaster train as the train leaves the chain lift to begin its second ride.
Eventually, the agents and Calder corner the bomber, who produces a radio control and threatens to use it to detonate the train. As the agents begin working on a way to jam the radio frequency signal, the bomber demands a firearm. Calder takes one from an agent and begins to hand it over to the bomber. As he does so, the other agents alert Calder that they have succeeded in jamming the detonator's signal. Calder hangs on to the gun, but as he does so it accidentally discharges and hits the bomber, who takes advantage of the ensuing confusion to run away. He jumps over a fence into the area below where The Great American Revolution rides and runs blindly. Eventually, the bomber circles back close to where Calder is and climbs onto the roller coaster's track. On the track, the bomber sees Calder and freezes, and is hit and killed by the train that he had tried to blow up (though we don't see the moment that he is hit, only his body thrown to the ground in the aftermath of the impact). After the bomber's body is taken away, the ride opens once again.
