The Riders discover a brand-new, frosty Ice Realm; once inside, they encounter Buzzsaw, who pretends to be a hurt hiker while trying to capture Thunder without the Riders finding out his true identity.
Alex and Eugene find themselves at odds with Tom and their fellow dragon riders when Feathers and Webmaster go missing during a blizzard in the Ice Realm.
Tom and Thunder discover a baby Night Light and must figure out how to return him to his home realm; things are complicated by the discovery of a clan of dragons who aren't trusting of humans.
Tom and the Riders vow to help Thunder face the dangerous dragon who attacked the King's Realm: a fierce and unpredictable Snow Wraith who has made its way from the Ice Realm.