Wartime bandleader Betty is in a predicament. Every time the Blonde Bombshells, the most glamorous swing band in the North, play a GI camp, they lose members. Four of her girls have gone AWOL, and with an important BBC radio engagement in the offing, Betty needs to find new musicians -- and fast. Among those who turn up to the hastily organised auditions are naïve schoolgirl Liz who plays a mean clarinet; Miranda, an uppercrust saxophonist; singing nun Lily, and Patrick, a male drummer prepared to don a frock in order to avoid a drafting. With her motley line-up complete, Betty and the band prepare to dodge Hitler's bombs and make the dangerous journey to far-flung Hull -- and potential fame and fortune.