Shining Through (1992)

In 1940, Linda Voss is a woman of Irish and Jewish-German parentage who loves the movies, especially films about war and spies. She gets a job at a New York law firm after it's revealed she can speak German fluently. As secretary and translator to Ed Leland, she begins to suspect that her boss is involved in espionage work. The two become lovers, and when America officially joins the Allies in fighting Hitler, Linda volunteers to go undercover behind enemy lines.