In the midst of World War II, when the navy WAVES gives Evelyn the chance to get out of Washington, DC, and contribute to the war effort, she can't leave fast enough. Mark figures the distraction the WAVES cause doesn't justify the assistance they provide. That is until a certain beautiful ensign offers suggestions that may help the engineers succeed in their mission. When the actions of a spy put both Mark and Evelyn under suspicion, will the investigation make their relationship another casualty of war, or will it bring about the birth of a true promise of love?