Growing up without the care of a loving family made Anna Golding fiercely independent. So when war breaks out, determined to do her duty, she joins the Women's Auxiliary Air Force. Her fellow trainees are like the sisters she never had. However, as they all talk of fond memories of home, Anna's heart breaks. Her past is too painful to share. Then she meets her friend's brother, Royal Air Force navigator Jimmy Armstrong, whose gentle care makes her feel safe for the first time in her life. Anna and Jimmy must snatch moments together as their duties pull them to opposite ends of the country, and every letter from him brings a thrill to her heart. But one day, a letter comes addressed to Anna that isn't in Jimmy’s handwriting. It's from an anonymous young woman claiming she knows a secret about Anna's mother . . .