Aston, a quiet, reserved man, lives alone in a top-floor cluttered room of a small abandoned house in a poor London district. He befriends and takes in Mac Davies, an old derelict who has been fired from a menial job in a café. In time Aston offers him a job as caretaker of the house. Aston's brother, Mick - a taunting, quasi-sadist - harasses the derelict when his brother is away, countermanding his orders...