A woman suffering from amnesia reconstructs her life from audiotapes and discovers that she has had a sordid past, involved in prostitution, and unusual romantic relationships.

In 1942 in occupied France, a Jewish refugee marries a soldier to escape deportation to Germany. Meanwhile a wealthy art student loses her first husband to a stray Resistance bullet; at the Liberation she meets an actor, gets pregnant, and marries him. Lena and Madeleine meet at their children's school in Lyon in 1952 and the intensity of their relationship strains both their marriages to the breaking point.

Doctor Valois has invented the "flashage", a cure for depressed people. After having tested it on monkeys, he tries with a first human patient, Alain Durieux. This is great success, everybody's happy except may be Alain's wife, Jeanne, who's worrying about the changes in Alain's personality. Other patients use the treatment with similar successes, and Valois's happy about it. But the monkeys are changing: non-cured ones are made mad by the over-stability and stereotyped behaviour of the cured ones. So are the humans. When Valois realises he can't stop the process, he decides to "flash" himself.

A homeless street musician meets an attractive woman by chance and keeps following her until he persuades her to let him stay in her place.