Barney Thomson, awkward, diffident, Glasgow barber, lives a life of desperate mediocrity and his uninteresting life is about to go from 0 to 60 in five seconds, as he enters the grotesque and comically absurd world of the serial killer.

Robert Carlyle
as Barney

Emma Thompson
as Cemolina

Ray Winstone
as Holdall

Ashley Jensen
as Detective Inspector June Robertson

James Cosmo
as James Henderson

Tom Courtenay
as Chief Superintendent McManaman

Kevin Guthrie
as MacPherson

Martin Compston
as Chris

Stephen McCole
as Wullie

Samuel Robertson
as Detective Sergeant Sam Jobson