A Yorkshire coal mine is threatened with closure and the only hope is for the men to enter their Grimley Colliery Brass Band into a national competition. They believe they have no hope until Gloria appears carrying her Flugelhorn. At first mocked for being a woman, she soon becomes the only chance for the band to win.

The absurd adventures of two defective detectives, who - despite unbelievable incompetence - somehow manage to solve their cases (or be nearby when the cases are solved) and retain their jobs.