Charles Rane, a notorious airplane hijacker, is about to undergo plastic surgery when FBI and police surround the building. Rane kills his doctor, jumps out the window, and a chase ensues before FBI agents capture the terrorist. Later, his attorney, Phillips, reveals Rane is being extradited to Los Angeles, California, to stand trial for two airline bombings, and agrees to notify Rane’s team of the travel plans. Meanwhile, John Cutter teaches an airline security class and berates flight attendant Marti Slayton when she takes an unnecessary risk during the hostage simulation. Airline executive “Sly” Delvecchio interrupts their argument and notes that his friend was too harsh with his critique of Marti. Sly offers Cutter a position as head of the airline’s new counterterrorism unit, but Cutter declines. Cutter was a security specialist with the airline until his wife’s death during a botched store robbery. Cutter and his wife, Lisa, were shopping when the robber ran inside, and when Cutter tried to intervene, the robber shot Lisa. Sly insists Cutter should stop blaming himself for Lisa’s death, and return to work. After consideration, Cutter accepts the position and is sent to Los Angeles to be introduced as the company’s new vice president at the annual stockholders meeting. Marti Slayton turns out to be the flight attendant on Cutter’s flight, and during her head count, she is unhappy to discover he is passenger number fifty-seven. Cutter is a nervous flyer and tries to get Marti’s attention, but she ignores him. Sabrina Ritchie, a new flight attendant, notes the situation and learns from Marti that Cutter is the airline security specialist. Charles Rane, escorted by two FBI agents, also boards the plane. After take-off, Cutter asks Marti for an aspirin, admits his discomfort flying, and asks for her assistance. Moments later, Marti seats a talkative elderly lady next to Cutter to keep him company. Soon, he needs a break from the woman, and excuses himself to hide in the bathroom. Flight attendant Sabrina telephones her cohort, Vincent, in the galley below, asks for “special service,” and is sent a briefcase in the elevator. Sabrina wheels the dinner cart to Rane’s aisle, pulls out a gun, and shoots the FBI agents. As Rane is freed from handcuffs, his team of terrorists take over the plane. Cutter observes the situation, and sneaks out of the bathroom to grab the mobile airline phone. Back inside the bathroom, he telephones Sly Delvecchio. Sly answers and overhears as a hijacker opens the bathroom door, discovers Cutter and they fight. When Cutter gains the upper hand, and holds him hostage in the aisle, Rane grabs Marti and puts a gun to her head. Rane notes that airline personnel assume a risk with their jobs, but passengers do not. He pushes Marti toward Sabrina and grabs a passenger named Douglas. Rane threatens to kill Douglas unless Cutter drops his weapon. Cutter does, but Rane still shoots Douglas. He aims at Cutter, who pushes a hijacker into the path of the bullet. As Cutter dives for the elevator, Marti breaks free from Sabrina and joins him. Unconcerned, Rane contacts Vincent in the galley below to alert him. However, Cutter prevails in his fight with Vincent, and knocks the terrorist unconscious. Meanwhile, Sly alerts the airline and FBI about the hijacking. In the cargo hold, Cutter tells Marti he will force the plane to land by dumping the fuel. As the plane descends, Rane orders the co-pilot to land at a small nearby airport. The airport is too small and refuses their request to land, but Rane insists, and the manager calls police. In the cargo hold, Cutter and Marti ready to jump out upon landing. However, Rane’s man, Mr. Forget, sneaks behind them, grabs Marti, and forces Cutter out of the plane as it lands. On the tarmac, two officers arrest Cutter, and refuse to believe he is a security officer. In the airport tower, Sheriff Biggs arrives and negotiates with Rane, who threatens to murder passengers until a refueling truck arrives. Rane promises to release half of the passengers when the plane is refueled, and Biggs agrees. The officers bring Cutter into the tower, and he insists that Rane has a history of creating distractions to hide his escapes and is fooling the sheriff. However, Biggs does not believe Cutter. Rane contacts the tower and claims that Cutter is a terrorist who escaped from the plane. Biggs believes Rane and orders his officers to take Cutter to jail. On the plane, Rane orders Sabrina to carry on with their plan, and she allows half the passengers to leave, while Rane and two of his accomplices sneak out through the cargo hold. As the officers lead Cutter outside, he sees the fleeing passengers and notices Rane sneaking away. Cutter breaks free from the officers, steals a motorcycle, and follows Rane and his men to a nearby fair. Sly Delvecchio and FBI agents arrive at the airport and inform Biggs that Cutter is not a terrorist. Meanwhile, Cutter chases the terrorists through the fairground, killing one on the ferris wheel. Rane stalks Cutter on the merry-go-round, but when he stops to reload his weapon, Cutter attacks him. Officers arrive to arrest Rane, and Cutter looks for his accomplice, Vincent, but cannot find him. Vincent changes into a paramedic’s uniform and escapes, as Cutter and Rane return to the airport with FBI agents. Rane insists that his team will murder the passengers unless he is returned to the plane. The FBI agrees, but has sharpshooters ready and Cutter, who knows the terrorists, will alert them to their targets. However, as two FBI agents lead Rane back to the plane, Vincent sneaks behind the sharpshooters, kills them, and shoots the two FBI agents. Vincent opens fire on officers surrounding the plane, and Rane gets back onboard and orders the pilot to take-off. Cutter shoots Vincent, and asks Biggs to drive him to the departing plane. Cutter jumps from the car onto the plane’s landing gear as it becomes airborne. He sneaks inside the cockpit and tells the pilot to return to the airport. As the plane turns around, Rane sends Sabrina to the cockpit to investigate. Cutter knocks her unconscious, arms the pilot with a weapon, and enters the main cabin to confront Rane. As the two men battle, Rane shoots out a window. Cabin pressure drops and a flight door opens. It is a brutal battle, but Cutter prevails and pushes Rane out the door. Marti and the passengers cheer as the terrorist plummets to his death. Reporters swarm as the plane lands safely, and Sly handles the press while Cutter and Marti leave together.