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.

Patrick Dewaereas Alain Durieux
Jacques Dutroncas Pierre Valois
Fanny Cottençonas Jeanne Durieux
Stéphane Audranas Édith
Philippe Léotardas Marc Lebel
François Dyrekas le responsable du zoo
Anna Gayloras une agent d'assurance
Jean-Paul Muelas le directeur furieux
Francis Lemaireas le directeur de l'usine
André Thorentas M. Borne