1950's. Being a pickpocket and trickster Knock and hiding from "colleagues" in a small French town Saint-Maurice, pretends to be a licensed doctor. He thinks out a clever, but at the same time simple plan, to stay without means of subsistence: to heal healthy people from non-existent diseases. Knock is the master of manipulation - almost reached the desired goal, if not for two small difficulties: he falls in love, and his friend from the past suddenly appears and intends to tell the whole truth about him.
