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

"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....

A single-volume omnibus of the three Cahill Files novellas, originally published as ebooks, explores the powerful Cahill family's roles in three high-profile historical events.

When the Vespers continue their abductions and cross a line by kidnapping Atticus, an eleven-year-old non-Cahill civilian and Dan's only friend, Dan and Amy confront their biggest challenge ever in order to keep Atticus alive.

A Clue found in Book 3 sends Amy and Dan jetting off to find out just what's behind the fierce rivalry between the Tomas and Ekaterina branches of the Cahill family. Was a Clue stolen from the Tomas branch? Where is it now? And most important, can Amy and Dan get their hands on it before their rivals do?

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.

When Bertie the badger visits his grandfather at a retirement home for magicians, he learns that his grandfather's rabbit, Enigma, has disappeared along with everyone's magical things, and the reader is invited to help break a code to find the items hidden throughout the book. Includes a built-in decoder

Kiki and her friends learn about coding as they compete to be the escort for young narwhal who will visit Trident Academy with her famous parents. Includes glossary, key to the codes used, and information about safeguarding narwhals' habitats.

"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"--

Akiko, Mae, and Josie, also called the Infinity Trinity, spring into action after learning that a spy is betraying secrets to the Japanese military--and that Akiko's mother may be involved.