THE PLOT:Los Angeles, October, 1993
Jack Traven (Keanu Reeves) and his partner Harry Temple (Jeff Daniels) are explosives experts in LAPD SWAT. An extortionist named Howard Payne (Dennis Hopper) is holding a group of office workers for ransom in an express elevator. Jack and Harry manage to rescue the hostages before Payne sends the elevator plummeting to the basement. They find Payne in a freight elevator. Payne holds Harry hostage, but after a brief standoff, Jack shoots Harry in the leg, causing Payne to release his hostage. Payne escapes and sets off a small explosion in the parking garage that knocks Jack unconscious and appears to kill Payne. Jack and Harry are then commended for their bravery by the LAPD in an official ceremony. Now with a crippled leg, Harry is promoted to Detective II and given a desk job.
Venice, June, 1994
It is almost eight months since the previous events occurred. After grabbing his morning coffee, Jack observes as a Santa Monica Municipal Bus Lines bus explode in front of him. Payne calls Jack on a nearby pay phone, revealing that he has rigged another bus to explode. Once the bus reaches 50 miles per hour, the bomb will be armed. If it drops below 50, it will explode. In addition, Payne will detonate the bus manually if anyone gets off the bus, or if the ransom is not delivered on time. To complicate matters even worse, the bus Payne rigs is an express bus running on the morning rush hour route into downtown, thus making an effort to stop the bus before the bomb arms futile. Jack locates the bus and jumps aboard, but the bomb has already been armed.
When Jack identifies himself as a police officer, one man draws a gun, believing Jack has come to arrest him. In an ensuing struggle, he accidentally shoots the driver, Sam (Hawthorne James). Another passenger, Annie Porter (Sandra Bullock), takes the wheel. Annie is left to drive the bus throughout the city while keeping it above the necessary speed and avoiding other cars. News of the bomb makes TV broadcasts and soon there is a long line of news choppers trailing the bus, which is routed onto the Interstate 105 freeway. Jack negotiates for the wounded bus driver to be evacuated from the moving bus. However, when Payne witnesses a terrified passenger named Helen trying to get off as well, he detonates a small bomb under the steps. This causes Helen to fall under the bus, where she is crushed to death beneath the wheels.
The bus comes to a 50 ft (15 m) gap in the freeway, but by increasing speed the bus launches over the gap. They drive to the Los Angeles International Airport where they can safely maintain their speed by driving in circles on the runway and, being a restricted airspace, the police can operate without the bomber seeing them in the media from the news helicopters. Jack goes under the bus on a sled in an attempt to defuse the bomb, but when the sled loses control, he tries to grab hold of the bus and accidentally ruptures the fuel tank with a screwdriver.
Harry and his team find several clues identifying Payne as the bomber, as it is revealed that Payne was once an Atlanta bomb squad sergeant who retired in 1989 after being severely injured (loses his thumb) while defusing a bomb, and being unsatisfied with the meager pension he received for years. They manage to locate and raid Payne's retirement residence, but Payne has already rigged the house with a bomb which explodes, killing Harry and his team.
Upon learning the deaths of Harry and his team, Jack discovers that Payne is monitoring the bus with a hidden camera. Using a news van, Mac and his colleagues loop the footage being transmitted to Payne. This allows them to safely evacuate the passengers to another bus. After Jack and Annie evacuate, the bus crashes into a fully fueled cargo plane and is destroyed in a spectacular explosion. Jack begins to fall in love with Annie, but she warns him that relationships started in intense situations tend not to last. Despite this, Annie starts to fall in love with him also.
.