Tony and Nanar, two teenagers who met in reform school, are part of a gang of idle, penniless youngsters from the Paris suburbs. Together, they go to dances and plan mischief. The muse of the gang, B.B. La Brune, organizes leisure activities when she's not up to no good. Unemployed and penniless, they all dream of consumption and possession. Until the day a fight turns ugly: Tony, trying to reason with Nanar, pulls the trigger.