Coy "Cannonball" Buckman, a former race driver turned parolee, finds himself on the path to chaos as he enters the Trans-Continental Road Race, a grueling cross-country competition that kicks off from Santa Monica Pier and concludes at a garage in New York City. This ambitious endeavor raises eyebrows, particularly from his parole officer girlfriend, Linda Maxwell, who is deeply concerned about the repercussions of his participation, knowing that any infraction could land him back in prison.
Fortunately, Coy has the support of his devoted friend, Zippo Friedman, who eagerly assists him by fine-tuning Coy's brilliant red Pontiac Trans Am. In a clever twist, Zippo decides to enter the race himself, disguising his participation by dressing up as Coy to evade law enforcement. However, the competition is fierce. Among Coy's adversaries is Cade Redman, a bitter fellow racer who has also been assigned to escort the untalented country singer Perman Waters and his mother Sharma Capri to New York City in hopes of reviving Perman’s stagnating music career.
Other notable racers include the eccentric European champion Wolfe Messer, who races in a vibrant yellow DeTomaso Pantera, and the surfer couple, Jim and Maryann Crandell, navigating the roads in a silver Corvette that belongs to Maryann's father. Meanwhile, Terry McMillan employs cunning tactics to reach the finish line without ever driving his orange Chevrolet Blazer. Beutell Morris uses the race as an elaborate cover to safely transport a wealthy couple's Lincoln Continental to New York, all while Sandy drives a custom blue van loaded with her two waitress friends, Judy and Ginny.
Unbeknownst to Coy, his gambler brother Bennie has placed a dangerous bet with mob boss Lester Marks to ensure Coy's victory, as he is deeply entrenched in debt. Reluctantly, Linda begins the race alongside Coy but soon decides to part ways when Redman starts a reckless assault on Coy's vehicle.
As the race unfolds, treachery escalates. Bennie conspires with an ex-con named Sharpe to sabotage Messer’s car with a bomb, which detonates during a frantic police chase across the desert. Amidst this chaos, Redman resorts to extreme measures, puncturing one of Coy's tires before physically confronting him in a supermarket, leading to a spectacular brawl that wreaks havoc throughout the store. Following this, Coy's journey becomes even more perilous when he totals his car on a treacherous mountain road but is momentarily saved by two supportive mechanics who loan him a green Ford Mustang.
Redman, now desperate to eliminate Coy, mistakenly beats up Zippo, thinking he’s Coy, while Linda stands her ground, fending off the attackers with awe-inspiring martial arts skills. In a shocking twist, Coy learns from Linda that Zippo once took the blame for a tragic incident involving a young girl that had resulted in Coy’s incarceration. As the race nears its conclusion, additional subplots unravel: Jim and Maryann struggle with their racing challenges, while Sandy and her friends utilize their charm to escape the clutches of law enforcement.
The climax arrives when Redman, pushed to his limits, pursues Coy into an unfinished bridge construction site where chaos ensues. After a nail-biting jump across the gap, Redman's reckless pursuit results in a fiery crash that seals his fate. Meanwhile, Sharpe's intentions to assassinate Coy with a sniper backfire catastrophically, resulting in Zippo’s tragic demise and further complicating the chaos.
As the road to victory becomes littered with wreckage, Jim and Maryann stumble upon Linda injured but safe, and after a series of mishaps, they ultimately take home the race win. However, for Coy, victory is bittersweet as he races to the hospital to be with Linda, learning of his brother’s betrayal along the way. In an emotional reunion, Coy holds Linda in his arms as the dust settles, the weight of the race's trials transforming their bond forever.
