It's the 1950s. Betty lives in a cold, two-roomed flat in a shabby Victorian house situated in a deprived area of Leeds. Her husband Donald is focused on saving to get them out of there.Betty's sick of struggling to keep the flat warm for her baby son Mark, and she's tired of trying to make ends meet. The only respite she gets from the day to day drudgery is the glamour of the Balula Dance Hall, which she visits once a week with her vivacious sister Margaret. But Betty's world is turned upside down when a handsome Polish man called Craze asks her to dance...