A gangster family epic set in 1919 Birmingham, England and centered on a gang who sew razor blades in the peaks of their caps, and their fierce boss Tommy Shelby, who means to move up in the world.

When a failing music venue staffed by fools looks set to close, manager Keith launches a last ditch Battle of the Bands competition. More by accident than by design, musical genius is unleashed by a rapping transvestite, some precocious indie rockers and a barmaid with a golden voice, who together try to save the world they love.