Balthazar Lamarck-Caulaincourt (Alain Cuny) is a bumbling middle-aged intellectual who spouts off from time to time about leftist causes, usually to his current girlfriend. Then Edwarda (Bernadette Lafont), who is active in the political underground, comes into his life. From that point on, he begins to act on his beliefs. Edwarda's underground political action group stages a little drama to test Balthazar's commitment and reliability, putting him through an interrogation by what appear to him to be French secret police. Having passed this test, he is given a real assignment.