Follows siblings Jakob Novis and his quirky younger sister Lizzie as they find themselves at Bletchley Park, the home of WWII codebreakers working to decrypt the Nazi's Enigma cipher, where the two struggle to unravel a mystery surrounding their mother's disappearance against the backdrop of the Battle of Britain and Hitler's feared invasion.
A cryptic message forces eighteen-year-old American Edda to investigate what secrets followed her across the ocean, even as she tries to make sense of her time as a telephone operator on the French front lines of World War I.
In the summer of 1940, siblings Jakob and Lizzie Novis find themselves at Bletchley Park, where Jakob works to crack Nazi codes while Lizzie investigates the mysterious disappearance of their mother, only to discover that the two mysteries are intertwined.
Amy and Dan find themselves in Vienna, where they search for clues while evading their enemies, and attempt to discover the truth about their famous ancestors, Wolfgang Amadeus Mozart and his sister Nannerl.
"Still reeling from the life-changing discovery he found buried in the mysterious archive, Cruz Coronado grapples with an important secret as the gang heads to China in search of the second-to-last piece of the cipher. Under the watchful eye of a new adviser, life on the ship returns to almost normal . . . Almost. Just as things seem to be going smoothly, a familiar face shocks Cruz back into reality, and the final piece in this life-and-death scavenger hunt veers toward a dead end"--Publisher.
Dan and Amy Cahill are given the choice of receiving a million dollars or uncovering the thirty-nine clues hidden around the world that will lead to the source of the family's power, but by taking on the clues, they end up in a dangerous race against their own family.
In 1666, after four months away, friends Christopher Rowe, Tom, and Sally return to London triumphantly but, guided by coded riddles, face a conspiracy that threatens Christopher, as well as the King himself.
657 days ago Meg's British father left their home in France to fight the Nazis, leaving some codes in a jar for her to decipher, and Meg and her French mother moved to the Perche, a region in France near Normandy known for its forests; now Meg watches the German soldiers in town, and sometimes carries messages for the French resistance--but suddenly things have gotten much more dangerous: there is a wounded British officer hiding in her grandmother's barn, a family of German refugees who are trying to get to Spain, and the Nazis have arrived on the doorstop searching for the fugitives.
Eleven-year-old Chester and his classmate Skye, tasked with a complex puzzle-solving mission, discover the key to their spy assignment is to stop a heist, but cracking the code could put them in serious danger.
"On an island nation in the Indian Ocean, the explorers venture through a vast underwater world and take part in a friendly robotics competition. But the tides of good fortune change quickly. Suddenly, Team Cousteau jumps into action to rescue a faculty member from the brink of death. Meanwhile, the team follows the Cruz's mother's clues to a magnificent tomb and center of spirituality precariously perched on the side of a cliff. There, Cruz is confronted by a familiar foe who's determined to stop him from completing his most important mission of all: Retrieving the final pieces of his mother's cipher. In this life-or-death showdown, Cruz witnesses the ultimate sacrifice and uncovers a hidden message that makes him question his own mortality"--Publisher.
