A black Porsche 911, license plate S-B 2795 cruises thru a quiet French countryside. A yellow tag in the windshield states "24 Heures 70" and the car enters a racetrack. The driver, Mike Delaney (Steve McQueen) gets out and stares at a spot behind the aarmco barrier. Flashback to a night race at Le Mans, a crash and explosion. Piero Belghetti in the 18 Ferrari is dead, Mike Delaney is hurt and taken away by stretcher. Lisa Belghetti (Elga Anderson) is stunned by the track announcement.
Titles. Scenes of Le Mans pre-race, campers, repairmen, sweepers. A medical van is set up. Police in force and a train arrives with many people. Many cars make their way to the track to huge parking lots. The #5 Ferrari 512 is offloaded as is the #22 Gulf Porsche 917. Drivers get dressed in nomex racing suits in their motorhomes, Erich Stahler(Siegfried Rauch), PJ Dion (JC Bercq), Mike Delaney, Johann Ritter (Fred Haltiner) with his wife Anna (Louise Edlind), and the young Claude Aurac (Luc Merenda).
At 3:30 pm the track announcer gives background info on the race, this is the 38th running. Delaney enters the car #20 pit looking at the expectant crowd. He gets his blue helmet. The German driver Erich Stahler checks out his Ferrari. Lisa Belghetti watches Delaney as he walks up the pit row. Stahler beat Delaney two weeks earlier at the Nurburgring. Delaney gets in the #20 Gulf Porsche.
After a tense final two minutes at exactly 4:00 pm the race starts! The 20, 25 and 21 Porsches take off followed by four Ferraris. The white long tail 25 Porsche takes the lead as David Townsend (Ronald Leigh-Hunt), the Gulf team manager grimaces. After awhile Stahler in the #8 Ferrari takes 2nd place but the 25 car has a large lead.
At 4:50 #25 comes in for fuel followed by all the other frontrunners. The drivers change out. Delaney and Stahler check their lap times. Mike says hello to Lisa as he goes to the rest area. The Ritters go to their trailer, Delaney to his. Anna makes her husband some tea, Johann hints he will be retiring. Rain starts. Mike sips his tea.
#25 retires with a blown engine, it was the fastest car at over 250 mph on the Mulsanne straight. The press grills Delaney and Stahler as they walk back to the pits. Both speak well of the other in mutual respect. The two men meet briefly and chat.
Two hours in #8 leads #20 as the twilight descends. The Three Porsche and four Ferraris stay out on dry tires. Townsend stares down his Ferrari counterpart. A yellow Lola #11 spins out and causes #47 911 following to also spin and stall in the middle of the track. The yellow lights come on and the cars bunch up but no one is hurt.
The Porsches and Ferraris come in for rain tires. Delaney gets away first and now leads Stahler. In the pits Claude Aurac chats to Lisa and offers her coffee. She politely begs off and leaves, walking sadly through the amusement park area.
At 2:15 am spectators wander about as the cars continue to race around. Mike gets out as does Erich, they each give their crews and teams feedback. Mike goes to a nice cafe for a buffet dinner. He notices Lisa sitting alone and joins her. They make small talk. Lisa asks Mike about the accident last year, he asks her why she came back. "for myself" she replies. They continue to chat in the quiet restaurant.
Dawn breaks still light rain. At 5 am #20 leads #8 by 12 seconds. 25 cars are left running. David is worried about the rear uprights as Mike gets back in his car. Stahler follows. #7 Ferrari also changes drivers.
Stahler spins out in the middle of the track. Claude Aurac in #7 comes around a corner and spins as he tries to avoid hitting the 8 car. #7 is launched into the trees, Claude manages to get out of the wreck just before it explodes. Farther ahead, Delaney notices the explosion over to his right side and is distracted. He almost rams a backmarker but has a massive shunt bouncing off the aarmcos. Mike gets out of the wreck and is helped by two track workers. A medevac helo comes and picks up Claude. Lisa hears the accident announcement as deja vu. An ambulance brings Delaney to the medical van. Aurac is brought also on a gurney and hooked to an IV, he is taken away by a larger ambulance. Mike is checked out by the doctor, he only has a cut lip. The press questions Lisa outside until Mike comes out and helps her get away.
Stahler pits for a new nose. A crewman tells him Claude is bad but will pull thru, Delaney is OK but out of the race. Mike returns to the pit and gives a racing tip to a younger teammate.
#22 pits. David asks Mike what happened, Mike admits he made a mistake. He takes his helmet bag and returns to his trailer. Lisa is outside and he brings her inside. The two talk and Mikes give her the "racing is life, everything in between is just waiting" philosophy. The drizzle continues.
#21 Porsche pits unexpectedly. It is jacked up and the crew begins to work on the rear suspension. #8 Ferrari is in the pits, Erich tries to leave but the car stalls. The Ferrari mechanics jump to work on the electrical problem. Townsend sizes up the situation and goes to Delaney's trailer, he asks Mike if he is fit and wants him to take over for Ritter. Johann is stunned to see Mike suited up, but he goes over and tells him the car is running good. Ritter then goes to Anna and tells her he didn't want it to end like this.
The new leader is the #5 Ferrari Lugo Abratte (Angelo Infante) . In 2nd place is the #22 Porsche Larry Wilson (Christopher Waite). Stahler leaves the pits. Delaney a few seconds later. Down the Mulsanne Stahler sees the Porsche catching him up in the rearview periscope. Soon Delaney is right behind the Ferrari, then they race side by side towards Porsche Curve/White House. Past the grandstand 8 and 21 are 9 seconds behind the leader.
21 now gets past. #5 the leader has a flat tire near Indianapolis, Abratte retires the Ferrari in disbelief. Wilson speeds past now in the lead with two minutes left.
21 and 8 are still fighting. 8 takes 2nd place and closes in on 22. All three leaders are in close. 21 slots in right behind 22, 8 seems to inch ahead, but 21 rubs him and won't let Stahler by. Larry Wilson in the 22 Porsche wins!, Mike Delaney is 2nd and Erich Stahler is third. The Gulf team is ecstatic and spray champagne. Mike and Erich acknowledge each other with smiles. David sips his champagne and thanks Mike. Delaney then walks toward Lisa at the edge of the crowd.