Subway (1985)

Fred is living in the Paris Metro system. He is blackmailing Helena, whose safe he has robbed. Fred has various 'friends' all living in this surreal setting. The Roller is a rollerskating bag snatcher and Big Bill is a 'strongman'. The blackmail and Freds relationship with Helena and her heavies make up the bulk of the plot but on the side are Freds attempts to start a band using buskers from the Metro.