The Twiggs are a typical working-class family: Sam (Jack Warner) and Mary (Marjorie Rhodes) are trying to bring their family up in the shadow of the Blitz whilst taking everything in good humour. Their neighbours Joe (Charles Victor) and Emma (Gladys Henson) are constantly in the Twiggs' house, borrowing a cup of sugar or using their Anderson shelter and between them the two working class families put the world to rights.

But when their daughter falls for an upper class RAF pilot the Twiggs are asked by his mother, Lady Diana Stephens to tell their daughter to call the romance off, as the social gap between the families is too large. Incensed by Lady Diana's offer of money, Sam Twigg throws her out of the house. But events take a sudden turn as the war enters the Twiggs' own living room. Will the two families manage to overcome their disdain for each other and let true love find its way?