At 5 in the afternoon, on June 21, 1961, Cléo bursts into tears at a fortune-teller’s. She’s awaiting the results of a medical exam. She fears she has cancer. Cléo goes back out on the street. Everyone looks at her. She’s beautiful, coquettish, impulsive. She buys a hat and takes a taxi home. For 90 minutes, as clocks mark the time, we will be with her every instant. Her housekeeper, lover and musicians understand nothing of her anxiety. She practices a song and its lyrics upset her. She goes out again, alone.

Fear awakens her. She begins to see others, people in the street, people in cafés, a caring friend.

She goes to a park to look at trees and meets a soldier at the end of his leave. The bond that forms between them, at this dangerous time in their lives, soothes Cléo. He accompanies her to the hospital before returning to the war in Algeria. They share a moment of grace on this, the longest day of the year.