ciphers

Amy and Dan must find the Outcast before he causes a nuclear meltdown.

"A trip to a museum to learn about ancient Egypt turns into a new case for the Code Busters when they discover that someone may be stealing artifacts and replacing them with cunning forgeries"--Provided by publisher.

During a class trip to Washington, D.C., the Code Busters have many opportunities to hone their sleuthing skills as they explore the International Spy Museum, the White House, and more, but when a classmate goes missing, a mysterious figure in a trench coat may be the key to solving the case.

Could the Mark Twain books hidden through Book Scavenger contain clues about the string of recent arson fires plaguing the city?.

When Iranian-American Kamran Smith learns that his big brother, Darius, has been labelled a terrorist, he sets out to piece together the codes and clues that will save his brother's life and his country from a deadly terrorist attack.

When a mysterious letter written in code arrives at King's house for his human, Kayla, he follows the trail of the person who left it.

Siblings Dan and Amy Cahill have managed to avert one disaster recreation threatened by the man who calls himself the Outcast, but they have mere days to learn where the Outcast will strike next. The clues are pointing them toward a disaster modeled after Hurricane Katrina.

Jax and Ethan must decode an ancient Greek cipher to uncover the location of two magical urns before the urns are used to remove all faith and love from the world.

When his math genius neighbor Ben manages to uncover the key to modern data encryption systems, Robert "Smiles" Smylie comes up with an idea to protect Ben from government agents out to steal the key. But while carrying out his plan, Smiles discovers that his own past may prove the greatest danger to both himself and Ben.