The inhabitants of the isolated Scottish island of Todday in the Outer Hebrides are largely unaffected by wartime rationing, until the supply of whisky runs out in 1943. Then gloom descends on the disconsolate natives. In the midst of this catastrophe, Sergeant Odd returns on leave to court Peggy, the daughter of the local shopkeeper Joseph Macroon. Meanwhile, Macroon's other daughter, Catriona, has just become engaged to a meek schoolteacher, George Campbell, although his stern, domineering mother refuses to give her approval.