If you ask Delphinia Baker, she’d tell you she has all the family she needs. Sure, her mom passed away when she was young, her dad is often away on deployment, but even though Del has never had anyone she can call her people, she has always had her grandmother—and that’s enough. Besides, having no roots just makes it that much easier when you have to move again. All of that changes, though, when Gramma falls ill and Del is sent to stay with her great-grandmother. Del has never even heard of Nana Rose, and she has no interest in spending the summer on a hot island off the South Carolina coast.

Milo Bloom, chess prodigy, has a secret: he doesn’t want to play chess anymore. If only he had the courage to tell someone. Instead, he blows a major tournament on purpose. The problem is, winning that tournament was a ticket to chess camp, and now his summer plans are shot. Enter Roxie, a girl he’s never met, who shows up at his door to tell him that he and his mom will be spending the summer in her “cat room” … what?

Seventh grade begins, and Kareem’s already fumbled it. His best friend moved away, he messed up his tryout for the football team, and because of his heritage, he was voluntold to show the new kid—a Syrian refugee with a thick and embarrassing accent—around school. Just when Kareem thinks his middle school life has imploded, the hotshot QB promises to get Kareem another tryout for the squad. There’s a catch: to secure that chance, Kareem must do something he knows is wrong.

Summer, 1940. Nineteen-year-old Jakob Novis and his quirky younger sister Lizzie share a love of riddles and puzzles. And now they’re living inside of one. The quarrelsome siblings find themselves amidst one of the greatest secrets of World War II—Britain’s eccentric codebreaking factory at Bletchley Park. As Jakob joins Bletchley’s top minds to crack the Nazi's Enigma cipher, fourteen-year-old Lizzie embarks on a mission to solve the mysterious disappearance of their mother.

Since Grandpa died, Dally’s days are dull and restricted. She’s eleven and a half years old, and her exacting single mother is already preparing her to take over the family business. Starved for adventure and release, Dally rescues a mysterious envelope from her mother’s clutches, an envelope Grandpa had earmarked for her. The map she finds inside leads straight to an ancient vault, a library of secrets where each book is a portal to a precise moment in time. As Dally “checks out” adventure after adventure she begins to dive deep into her family’s hidden history.