When a mysterious little free library (guarded by a large orange cat) appears overnight in the small town of Martinville, eleven-year-old Evan plucks two weathered books from its shelves, never suspecting that his life is about to change. Evan and his best friend Rafe quickly discover a link between one of the old books and a long-ago event that none of the grown-ups want to talk about. The two boys start asking questions whose answers will transform not only their own futures, but the town itself.

Twelve-year-old Dory Byrne lives with her brothers on New York City's Lower East Side, waiting impatiently through the darkest hours of World War II for her pop to come home from fighting Hitler. Legally speaking, Dory's brother, Fish, isn't old enough to be in charge of Dory and her younger brother, Pike, but the neighborhood knows the score and, like Pop always says, "the neighborhood will give you what you need." There's the lady from the bakery, who saves them leftover crullers. The kind landlord who checks in on them.

Twelve-year-old Lidia is outside her grandfather's house when planes fly overhead, bearing the Nazi cross on each wing. Before the bombs hit the ground, Lidia realizes her life is about to change forever. Poland has fallen under German occupation, and her father makes the brave decision to join the Polish army to fight against the Nazis. Lidia wants to follow him into war, but she's far too young, and she's needed by her mother and brother. After her family returns to Warsaw, Lidia continues to play the piano, but she also wants to aid the Jewish people held captive in the Warsaw Ghetto.

When Aviva Davis and Holly Martin meet at the holiday pageant tryouts for their local senior’s center, they think they must be seeing double. While they both knew they were adopted, they had no idea they had a biological sibling, let alone an identical twin! The similarities are only skin deep, though, because while Aviva has a big personality and even bigger Broadway plans, Holly is more the quiet dreamer type who longs to become a famous author like her grandfather.

Vera Wong is a lonely little old lady—ah, lady of a certain age—who lives above her forgotten tea shop in the middle of San Francisco’s Chinatown. Despite living alone, Vera is not needy, oh no. She likes nothing more than sipping on a good cup of Wulong and doing some healthy detective work on the Internet about what her Gen-Z son is up to. Then one morning, Vera trudges downstairs to find a curious thing—a dead man in the middle of her tea shop.