As World War II breaks out, four friends consider the changes that war will mean. Tomboyish Becky plans to join the ATS, her neighbours Bob and Jim the navy and army respectively. Only Becky's brother Will is left out of the excitement; because of a slight physical disability, he is forced to stay behind. As the friends are separated, their youthful enthusiasm is tempered by the grim newspaper headlines and their own experiences, and they will feel both joy and pain before the war is over.