The hero of Le Desert de Pigalle is Janin (Pierre Trabaud), a two-fisted priest assigned to the lawless district of Pigalle. Janin takes it upon himself to reform the prostitutes in the area, which makes him extremely unpopular with the local "mecs" and white slavers. His toughest reclamation project is jaded whore Josy (Annie Girardot), but once he's won her over, she helps him to realize his goal with the other ladies of the evening.
Source : allmovie.com