Claude Goretta got his idea for Pas si méchant que ça from two news stories: one about the head of a Swiss business in financial difficulties who could only pay his employees by staging hold-ups, and the other of a man who kidnapped the son of a CEO by making him laugh by dressing up as Pinocchio. The idea is that, well, the robber here, Pierre (Gérard Depardieu), tries to calm his victims by showing them that he's not as nasty as that.
Pierre and his wife Marthe (Dominique Labourier) are living a comfortable bourgeois existence in the family woodcraft business which his father (until illness and death) has always been in charge of. And then things go wrong, the artisanal practice is menaced by plastic. But Pierre doesn't want to sack anyone, he'd rather rob businesses than that. And then one day he robs a post office, fires a shot at the ceiling and Nelly (Marlène Jobert) faints. Pierre rushes over the other side of the counter to help her and that's the start of a weird friendship. How was she to know that the gun was no longer loaded?
Eventually they become lovers, she – much to his disgust – even carries out a hold-up herself, heavily disguised and holding up an instruction card to hide her sex. Pierre's leading a double life, both very separate from the other. Until he's inevitably caught and the two women can only look on as the police arrest him.