When Hearts Are Light Again — Emilie Loring

Forsaking glamorous wartime Washington, lovely young Gail Trevor came home to work as secretary in the local defense plant. Unexpectedly, Captain Greg Hunt also returned on a secret mission to unmask a dangerous saboteur.
Although Greg was engaged to Lila Tenny, the town's leading socialite, it was Gall he asked to help him in his perilous man hunt. As the tension-packed days passed, Gail found her admiration for the handsome young captain turning into a deeper emotion. Could she hope that one day he would return her love?