| Director | Louis Malle |
|---|---|
| Box office | $263,404 |
Lovers Florence Carala and Julien Tavernier devise a plan to kill Florence's husband Simon, a wealthy French industrialist who is also Julien's boss. Staying late at the office one Saturday, Julien, an ex-Foreign Legion parachutist and veteran of the Indochinese and Algerian wars, climbs the side of the building to Simon's office and kills him with his own gun, then stages the body as a suicide. He leaves the building with a secretary and security guard to provide alibis. He glances up from his car and realizes he left his climbing rope hanging from the balcony rail. Leaving the engine running, he rushes back into the building and boards the elevator just before the security guard switches off the power and locks up for the weekend, trapping Julien between floors.
Louis, a young small-time crook, and his girlfriend Véronique, a flower shop assistant, steal Julien's running car and drive past Florence, who is waiting for Julien at a nearby café. The sight of Véronique convinces her Julien abandoned their plan and picked up another girl and she wanders the streets despondently searching for him in local nightclubs.
Louis and Véronique drive around for hours, until some Germans in a sporty Mercedes challenge Louis to a race. He follows them to a motel, and the German driver, the jovial Horst Bencker, invites Louis and Véronique to have a drink with him and his wife Frieda. Both couples check in and, while they chat, Frieda takes a few pictures of Louis and her husband with Julien's camera. She finishes the roll, so Véronique drops the film off at the motel's photo lab.
After the Benckers go to bed, Louis is caught by Horst attempting to steal the Mercedes, and Louis empties Julien's pistol into them. He and Véronique return to Véronique's apartment in Paris and Véronique persuades Louis to attempt suicide with her by taking phenobarbital pills.
The police discover the French couple at the hotel registered as "Mr. and Mrs. Julien Tavernier" and find Julien's car and gun next to the Benckers' corpses and Julien's raincoat in their stolen Mercedes. They search Julien's office, escorted by the security guard, and discover Simon's body. Once the building's power is switched back on, Julien escapes from the elevator and goes to a cafe, unaware that he has been identified as a murder suspect in the morning newspapers. He is arrested and charged with the murder of the Benckers, unable to convince the police that he was trapped in the elevator all weekend. The rope he left attached to the balcony eventually falls loose on its own.
Florence obtains Véronique's address from the florist and finds Véronique and Louis still alive. She accuses the drowsy couple of murdering the Benckers and calls the police with an anonymous tip. Louis believes he's gotten away with the murder when he sees Julien's picture in the paper, but Véronique reminds him of the roll of film. Louis rushes to the motel's photo lab, tailed by Florence, and is arrested on the spot. Inside the lab Commissaire Cherrier shows Florence the photos of her and Julien that have been developed and are now evidence against them. Cherrier informs Florence she will probably get a harsher sentence than Julien, and Florence replies she did it for love and believes she will one day be reunited with Julien.