After a successful bank robbery, Micky hopes to take back his girlfriend Marie who has been taken from him. On the way to Paris he meets Leon, a neurotic dreamer whom he considers an idiot. Leon can hardly understand what Micky is up to but he follows him everywhere and soon falls in love with Marie.

For Pierre Brochant and his friends, Wednesday is “Idiots' Day”. The idea is simple: each person has to bring along an idiot. The one who brings the most spectacular idiot wins the prize. Tonight, Brochant is ecstatic. He has found a gem. The ultimate idiot, “A world champion idiot!”. What Brochant doesn’t know is that Pignon is a real jinx, a past master in the art of bringing on catastrophes...