September 1942. Having done her duty as an ATS girl, Lance Corporal Ruth Cox is moving on to new challenges and has signed up to work as a gunner girl, helping to keep the skies clear of enemy planes and safe for our brave boys in blue. But on the way to her new barracks, Ruth meets handsome Sargeant Sam Johnson. Ruth isn't looking for romance, and she knows she has a dangerous job ahead, but there is a connection between her and Sam that she can't deny. Sam has never met anyone quite like Ruth before and he hopes their relationship will continue to grow, but with the war still raging, the time they have together is fleeting. It isn't long before they are sent to different parts of the country to do their duty and risk their lives. Will they find their way back to each other, or will war destroy their hope of happiness?