Victor Derval is returning home after a performance when he is hailed by Lisa, a young Hungarian woman. Her motives are mysterious; is she simply a star-struck peasant girl, or an ambitious, manipulative aspiring star?

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.

Two friends, Philippe and Jeannot, are drafted the same day and assigned to the same place. They have no taste for military life and during the conscription visit they try all they can to be declared unfit for service. They fail and land in barrack room 13, where a bunch of other "rebels" is gathered together, under the approximate control of a stupid warrant officer and a depressing captain.They all still have hopes of returning home soon.Besides Philippe and Jeannot, this motley crew consists of a rich allegedly kleptomaniac snob, a phony queen, an orthodox Jew, a yogi, a hippie, a Belgian, a hermetic poet, an Arab, and that's not the half of it...