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.

Nearly two years ago, Meg Kenyon's father left their home in France to fight for the allies in World War II. Recently, Meg heard he had been taken prisoner by the Nazis. All Meg has left of him now are the codes he placed in a jar for her to decipher, an affectionate game the two of them once shared. But even those are running low. But the codes are running low, and soon there'll be nothing left of Papa for Meg to hold on to at all. Suddenly, an impossible...

Chronicles the first Vesper attack on Jan van Eyck's altarpiece at Ghent in the 1600s, then jumps to WWII and young Grace Cahill's desperate bid to save the masterwork from the Nazis.

Ruby Redfort is a genius code-cracker, a daring detective, and a gadget-laden special agent who just happens to be a 13-year-old girl. She and her slick side-kick butler, Hitch, foil crimes and get into loads of scrapes with evil villains, but they're always ice-cool in a crisis.

When a rare coin and a strange code are uncovered in McKenna School, Malcolm and the other classroom pets of the Midnight Academy take on their most challenging assignment yet and, through their investigations, they just might save the school from closing.

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 Matt the Brat forms his own club, Cody and the other Code Busters gear up for competition.

When a new book arrives at the library with a secret code written inside, Derek, with the help of his friends, follows the clues from one novel to the next and makes a discovery that may help him get past a terrible loss.

Amy and Dan Cahill have their final confrontation with twisted billionaire J. Rutherford Pierce, a man whose power has no limits and is one step away from being elected president.

Thirteen-year-old Dan Cahill and his older sister, Amy, thought the search for the thirty-nine clues leading to the source of their family's power was over, but when Cahills are kidnapped by the Vespers, Amy and Dan find themselves with only a few day to fulfill a bizarre ransom request before their friends start dying.