A reclusive lighthouse worker accepts the offer to swap jobs with a police inspector for a while, just to help him catch Teston, the so-called criminal of criminals.
Ewa Bonecka, a young student about to start school in a new place finds herself without a place to sleep after she is declined a room in a women-only hotel. Helped by a pleasant policeman, Piotr, she tries to find a lodging in the strange town full of thieves and petty troublemakers.