When his gift for pickpocketing is noticed by the mysterious Finn Argos, Colm begins training to become a member of Thwodin's Legions, a strange group of warriors, mages, and hunters who search for treasure.

After witnessing a troupe of pickpockets pull off an incredible robbery in a busy Marseille square, Charlie Fisher agrees to protect one of the thieves if they teach him their ways, leading him into a world of adventure with global stakes.

Helping in a case their father is working on, the Hardy brothers try to find an informer who has telephoned from a booth in their home town, and are hired by a carnival owner to spot pickpockets.

"Pip lives by his wits in the city of Clarel. But when he picks the wrong pocket, Pip finds himself in possession of a strange dried heart in a silver casket--and those who lost it will stop at nothing to get it back. With assassins on his trail and the ominous heart beginning to whisper to him, Pip and his childlike older sister El are drawn deeper into the forbidden world of magic. Now they must seek the help of the secret witches of Clarel and...