Cotton Malone battles a group of families whose influence dates back to the American Revolution and who seek to crack a code devised by Thomas Jefferson himself in their quest for power.

A million dollars, or a clue? Police report a break-in at an elite hotel, and the suspects sound suspiciously like Amy and Dan. There's a car and speedboat chase and an angry mob! When there's a clue on the line, anything can happen.

An escalating race to find the 39 Clues finds Amy and Dan pursuing a Clue guarded by thousands of the world's best-trained soldiers, an effort that separates them in explosively dangerous ways.

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,...

What would happen if you discovered that your family was one of the most powerful in human history? What if you were told that the source of the family's power was hidden around the world, in the form of 39 clues? What if you were given a choice - take a million dollars and walk away ... or get the first clue? If you're Amy and Dan Cahill, you take the clue - and begin a very dangerous race.

Amy and Dan, wanted by the Indonesian police and stranded on an island with a tropical storm on the way, are about to discover a terrible truth about their branch of the Cahill family.

Bertie Bradshaw never set out to become a spy. He never imagined traipsing around war-torn London, solving ciphers, practicing surveillance, and searching for a traitor to the Allied forces. He certainly never expected that a strong-willed American girl named Eleanor would play Watson to his Holmes (or Holmes to his Watson, depending on who you ask). But when a young woman goes missing, leaving behind a coded notebook, Bertie is determined to solve...

Tensions run high in the explosive 8th book of 39 Clues, the #1 New York Times bestselling series. One belief has sustained fourteen-year-old Amy Cahill and her younger brother, Dan, on their hunt for the 39 Clues: They are the good guys. But then a shocking discovery about their parents shatters everything Amy and Dan think they know, dividing the two siblings for the first time ever. When Dan disappears in a country of more than a billion people,...

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...

"Amid assignments that take the Explorer Academy recruits from the iceberg-filled waters of Antarctica to the bone-dry deserts of Argentina, Cruz Coronado is scrambling to complete the last piece of the cipher. With Nebula agents and the elusive explorer spy still out there, his opportunity to recover his mother's world-changing formula is slipping away. But as Cruz has learned from his time aboard Orion, true explorers must never give up. Even after...