Growing up in rural Scotland, Tonia and her sister Lou rely on each other for everything. But when Lou leaves home at age 18 to get married, Tonia finds herself facing the world on her own for the first time. Accepting a marriage proposal from a kindly older man finally gives Tonia the independence she craves, and soon she's off to London with her new husband. But with the onset of WWII, the city is suddenly filled with chaos. Tonia finds herself in the midst of a war and filled with a sense of purpose she never had before.