American Michael Delaney (Steve McQueen) is a co-driver for Gulf Team Porsche during the grueling Le Mans endurance race. In the race, cars are driven for 24 hours over a 14.5 kilometer course, with the drivers swapping out every few hours, a challenge for both vehicles and their crews. Delaney has two forces tearing at him this time, German rival Erich Stahler (Siegfried Rauch) of Team Ferrari, and close friend Lisa Belgetti, whose husband was killed the year prior in an accident that was Delaney's fault.