Paris, 1939. Young and ambitious Odile Souchet has it all: her handsome police officer beau and a dream job at the American Library in Paris. But when the Nazis march in to occupy the city, Odile stands to lose everything she holds dear, including her beloved Library. Together with her fellow librarians, Odile joins the Resistance with the best weapons she has: books. When the war finally ends, instead of savoring freedom, Odile tastes the bitter sting of unspeakable betrayal. Montana, 1983. Lily is a lonely teenager looking for adventure in small-town Montana, and the air of mystery about her solitary, elderly neighbor from Paris piques her interest. As Lily uncovers hints about her past, she finds that they share a love of language, the same longings, and the same intense jealousy, never suspecting that a dark secret connects them.