Michael Bannon (Michael Sarrazin), a wealthy but bored businessman and candymaker, issues the code word "Gumball" to his fellow automobile enthusiasts, who gather in a garage in New York City to embark on a coast-to-coast race "with no catalytic converter and no 55-mile-per-hour speed limit," in the shortest amount of time and only one rule: "There are no rules." Their nemesis, LAPD Lieutenant Roscoe (Normann Burton), also learns of the race and most of the film is devoted to the adventures of the various driving teams and Roscoe's ineffectual attempts to apprehend them. A number of running gags ensue – the Jaguar that will not start; the silent Lapchik's (Harvey Jason) numerous mishaps; Italian race driver Franco Bertollini's (Raúl Juliá) frequent detours to seduce beautiful women – as well as some stunts and driving sequences. The race ends at the Queen Mary in Long Beach, California where the finishers celebrate their adventures and the defeated Roscoe sulks off to one side – until a fleet of police cars and tow trucks, summoned by Roscoe, arrive to impound the Gumball vehicles. Roscoe had contrived to see to it that all of them were guaranteed to be illegally parked once the post-race party in the parking lot ran past 11 PM. Bannon congratulates Roscoe on his final victory (final because Roscoe, who has been after Bannon and Smith since they were in high school, has reached mandatory retirement) and again utters the command "Gumball" to initiate a race back to New York.
Bright lights descend from the night sky, tracing routes over four desert highways, eventually converging on an isolated crossroads. Lightning flashes and blue smoke are the result of their high-speed collision, revealing a sleek, all black Dodge M4S Turbo Interceptor, driven by a black-clad and helmeted figure.
An assortment of people gather at a countryside inn in preparation for the infamous "Cannonball Run," an illegal three-day cross-country race from Washington, D.C. to Santa Monica where the winner and five runners-up will receive $1 million. However, the hot-headed Washington chief of police Spiro T. Edsel (Peter Boyle), along with his long-suffering sidekick Whitman (Don Lake), arrests all of the drivers to prevent the race from happening. As a result, sponsors must find replacement drivers by the next day.
Mike McCoy (Elvis), the lead singer for a traveling band who is also a part-time race car driver, enjoys his carefree single life, which is threatened by three different women who seek to marry him.
Racing driver Mike Brannan (Clark Gable), has a reputation for doing whatever it takes to win. Powerful nationwide columnist Regina Forbes (Barbara Stanwyck) decides to interview Brannan just before a race, and becomes annoyed when he is rather brusque with her. Brannan and popular competitor Joe Youghal fight for the lead. When a car they are about to lap crashes in front of them, Brannan safely drives around it on the inside, forcing Youghal to try to go outside. In her column the next day, Regina blames Brannan for Youghal's death and brings up a prior racing fatality involving him. As a result, he is barred by nervous racing circuit managers anxious to avoid bad publicity.
When an undercover detective is shot dead while investigating a string of Porsche 911 thefts, Lieutenant Vincent Bracey (Randy Quaid) assigns 22-year-old San Diego officer Benjamin "Benjy" Taylor (D. B. Sweeney) to infiltrate a Porsche garage suspected to be a front for the grand theft auto scheme. Benjy is chosen because of his extensive mechanical knowledge of German cars and his rookie status, which dissuades others from suspecting that he is a cop. Bracey wants Benjy to obtain evidence that millionaire playboy Ted Varrick (Charlie Sheen) is the mastermind behind the thefts and the murder of the detective.
A racing team run by Pat Kazarian starts out with two drivers, Mike Marsh and Jim Loomis, but a crash at Daytona results in Jim's death. His girlfriend Holly McGregor arrives too late for the race and feels guilty for not being there.
After serving in Europe during World War II, Herbie Brown (Lou Costello) and Slicker Smith (Bud Abbott) return to the United States aboard a troop ship. Also onboard is their old nemesis, Sgt. Collins (Nat Pendleton). As the ship nears New York, Collins and his superiors search the men's belongings for contraband. A six-year-old French orphan, Evey (Beverly Simmons), whom Herbie and Slicker befriended, is found in Herbie's duffle bag. She is handed over to Lt. Sylvia Hunter (Joan Fulton), who delivers her to immigration officials in New York. However, during a shift change at the office, Evey is mistaken for a neighborhood kid and set free. Meanwhile, Herbie and Slicker are back to their pre-war occupation of peddling ties in Times Square. Collins is also back at his old job--a police officer assigned to the same beat. He is about to arrest the boys when Evey shows up and helps them escape.
Amateur inventor Joe Belden has his Indiana hometown in a tizzy over his new "horseless carriage" in 1895. It runs on gasoline, but the townspeople aren't impressed and only Joe's mom and his sweetheart Liz Bullitt are supportive.
Steve Grayson (Elvis) is a generous NASCAR race car driver who feels compelled to bail friends and acquaintances out of financial hardship. However, Steve's manager Kenny Donford (Bill Bixby), a compulsive gambler, had been mismanaging Steve's winnings to support his gambling habits, landing Steve in deep trouble with the IRS for nonpayment of back taxes. This proves to be a problem for Steve in his efforts to continue racing competitively and support those who depend on his generosity.
Stock car racer "Fireball" Dave Owens from California goes to race in Spartanburg, South Carolina, where he intends on competing against local champ Sonny Leander Fox. Dave beats Leander in a race, impressing the latter's girlfriend, Jane, and the wealthy Martha Brian.
Racing life between Zack (Syamsul Yusof) and Sham (Farid Kamil) has not ended yet. Zack, who used to be an illegal racer is currently a professional drifter. After the accident, Sham no longer drifts due to his broken leg and has to walk using the aid of crutches. Soon a female professional drifter called Aleeya (Scha Al-Yahaya) appears. Joe (Aaron Aziz), who managed to escape unhurt from the accident, wants revenge on Zack. Joe’s assistant Ery (Shaheizy Sam) also wants revenge on Zack because he caused his best friend to get locked up in jail. Joe wants to control the whole drug business syndicate in KL, and Inspector Kamal (Remy Ishak) suspects him for the crimes that involved deaths.
A new science teacher, Miss Sandra Beecher, (Halle Berry) at Kona Pali High School in Hawaii pushes a group of students to come up with a science project. With a combination of design vision, mechanical skills, knowledge of batteries, and lightweight drivers, the students design and build a solar-powered car they name "Cockroach." Their team manages to outperform a corporate-sponsored car and win the local Big Island competition by correctly predicting cloudy weather based on the surfing experience of the student captain, Daniel (Casey Affleck). Cloudy weather would make their vehicle's battery capacity a more important factor than its weight.
Undercover police officer Lucas White enters the world of underground street racing to join a gang of street racers led by Vin Serento to get closer to a crime ring led by Los Angeles kingpin Juan Carlos de la Sol. The morning after losing a street race, Lucas goes to Vin's garage with a wrecked Smart Fortwo and lands a job as a mechanic, despite objections by Vin's friend Curtis. He also develops a relationship with Vin's sister Jordana.
Race-car driver Gino Borgesa meets a ballerina, Nicole Laurent, whose pet poodle causes a crash at the track. She persuades an ex-lover to give Gino money for a new car. They begin a romance, although Gino warns her that his racing comes first.