Fourteen-year-old Bobby Pendragon is not like other boys his age. His uncle Press is a Traveler, and, as Bobby has learned, that means Uncle Press is responsible, through his journeys, for solving interdimensional conflict wherever he encounters it. His mission is nothing less than to save the universe from ultimate evil. And he's taking Bobby along for the ride.

Fifteen-year-old Bobby Pendragon is a loyal friend, sports star, devoted pet owner - and Traveler. Along with his uncle Press, Bobby has visited the alternate dimension of Denduron and participated in a civil war. He's also waded through the endangered underwater territory of Cloral. Now Bobby once again finds himself thrust beyond the boundaries of time and space into a place that seems somewhat familiar: First Earth.

The territory of Veelox has achieved perfect harmony. Fifteen-year-old Bobby Pendragon arrives on this territory in pursuit of the evil Saint Dane, but all is peaceful on Veelox - because it's deserted. The inhabitants have discovered a way to enter their own personal dream worlds, where they can be whomever they want, wherever they want. Their bodies lie in stasis while their minds escape to the dream realm.

Just when 15-year-old Bobby Pendragon thinks he understands his purpose as a Traveler - to protect the territories of Halla from the evil Saint Dane - he is faced with an impossible choice. The inhabitants of Eelong are in danger of being wiped out by a mysterious plague. Only Bobby knows how to stop it, but it means bringing the antidote from another territory - Cloral.

The struggle of good versus evil continues as Bobby Pendragon follows Saint Dane to the territory of Zadaa. Saint Dane's influence has fueled the fire of discontent between two warring tribes: the Rokador and the Batu. This is also the territory where the Traveler Loor lives as a member of the Batu. Together she and Bobby must work to thwart Saint Dane's efforts to destroy Zadaa.