Françoise Barnier, the film's heroine, is a mother. One day, she stole something. She was in dire straits but no more so than usual. She was not in debt. She had always refused the degradation of excessive debt and charities, attempting to live in line with the rules laid down by society and the law. We follow her journey through the judicial institution. Here, two ideas of justice and law collide.

One fine day, at about 10 am, in a suburban house, three men, in their thirties are waiting for a fourth buddy. When he arrives, they plan to hold up the local bank where Séverine, their accomplice, is waiting for them. This could well be the beginning of a thrilling crime story, but these tough men, sporting tattoos, are not what they appear. "On fait comme on dit" is a comedy, and these guys could be descendants of the Keystone Cops. They are dreamers not gangsters. So much is riding on this bank heist, the pressure is intense. This tension creates the most diverse and unexpected obstacles for them...