Robert Carlyle plays Barney Thomson, a downtrodden barber who has fallen from grace in his meagre barbering life. One day whilst almost losing his job, Barney comically falls into the unthinkable role of a serial killer. As he sweats out his predicament, and attempts to clumsily cover his tracks, a police detective investigating a series of murders in the area begins to suspect Barney may not be all he appears to be. All the while Barney's mother Cemolina cheerfully emasculates her son, setting off a bloody chain of events.