A middle-aged alcoholic is sentenced to six weeks in jail for a minor offense. While there he undergoes psychiatric treatment for his alcoholism and is committed to a hospital for the criminally insane for the duration of his sentence. However, under Section 27A of the Queensland Mental Health Act, he can be detained indefinitely until the hospital authorities declare him eligible for release.

A schoolteacher, stuck in a teaching post in an arid backwater, stops off in a mining town on his way home for Christmas. Discovering a local gambling craze that may grant him the money to move back to Sydney for good, he embarks on a five-day nightmarish odyssey of drinking, gambling, and hunting.