Johnny and Adam are teenage surfers who live in Los Angeles with their father, Mac. Two weeks before Johnny's 16th birthday, ninjas attack the teenagers, but they are defeated by Zatch, a mysterious warrior with an eye patch. A follow-up attack results in Mac's kidnapping, though Zatch is able to protect the teenagers and their friend Iggy from the ninjas. Adam discovers that the video game on his Sega Game Gear matches the events happening around him and finds he can control some events through his Sega. Zatch reveals to Johnny and Adam that they are actually the sons of the king of Patusan, whose land and monarchy was overthrown by the evil Colonel Chi when the boys were young. It is their destiny to return to Patusan, overthrow Colonel Chi, and free the people. Zatch takes them to the Patusani district of "Little Patusan" in Los Angeles, where Johnny is introduced to a Patusani princess, Ro-May, who has been betrothed to Johnny since they were infants.