Fifteen-year-old Jason and Caroline Peterson fly with their dad to the Azores for an exciting outdoor-adventure vacation. However, after being lured away from their father and into the side of an extinct volcano, the twins accidentally pass through a time portal, suddenly finding themselves prisoners of strange, brutal men in the walls of a very active volcano. They discover from the other prisoners that somehow they have traveled back to the time of Atlantis when it was the center of a thriving civilization. Although they manage to escape, they jump from the frying pan into the fire. This continent is ruled by intelligent dragons that harbor a dark and deadly secret. If the twins can't find a way to stop them, these cruel creatures will not only alter the course of history but change the face of the earth forever.