Scholar Jules Addison and scavenger Amelia Radcliffe join forces to unravel secrets of a long-extinct civilization, only to discover something that could spell the end of the human race.

Thirteen-year-olds Bertie Bradshaw of London and American Eleanor Shea team up to decipher a coded notebook and stop a double agent from revealing secrets about the upcoming D-Day invasion.

As the race to find the 39 Clues builds to its explosive finish, Amy and Dan must explore an ancient culture and steal a Clue guarded by thousands of the world's best-trained soldiers. It's the most dangerous Clue search yet ... and it may mean the end for Amy and Dan.

While working at Bletchley Park transcribing decrypted signals from the German Army as it marches into Leningrad, Honey Deschamps begins to receive mysterious packages from Russia containing small pieces of amber that suggest a coded message.

"A strange telegram lures fourteen-year-old Amy Cahill and her younger brother, Dan, deep into Russia and away from the only trustworthy adult they know. Signed with the initials NRR, the telegram launches a race to uncover a treasure stolen by the Nazis and the truth behind the murder of the last Russian royal family. All too soon, the treasure hunt starts to smell like a Lucian trap. But the bait might just be irresistible--what will Amy and Dan...

Throughout the hunt for the 39 Clues, Amy and Dan Cahill have uncovered history's greatest mysteries and their family's deadliest secrets. But are they ready to face the truth about the Cahills and the key to their unmatched power? After a whirlwind race that's taken them across five continents, Amy and Dan face the most the difficult challenge yet -- a task no Cahill dared to imagine. When faced with a choice that could change the future of the world,...

"You are looking at the book Ex Libris by Matt Madden. Maybe you came looking for it; perhaps you just came across it in a bookstore or at someone's house. Or maybe you are reading this in a catalog on a screen. What kind of adventure do you think takes place on these pages? To judge by the cover design and the title, it appears books themselves are a subject of this volume. Does it have a comic book as its hero? If you put the book down now, you'll...

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.

When twelve-year-old Steve Brixton, a fan of Bailey Brothers detective novels, is mistaken for a real detective, he must elude librarians, police, and the mysterious Mr. E as he seeks a missing quilt containing coded information.

After being taught in a boarding school run by whites that Navajo is a useless language, Ned Begay and other Navajo men are recruited by the Marines to become Code Talkers, sending messages during World War II in their native tongue.