For 800 years, Norrisville High School has been protected by a ninja, with a new one chosen every four years. Freshman Randy Cunningham is selected as the latest ninja, tasked with the great responsibility of protecting everyone. Long ago, the original ninja sealed away an evil sorcerer using the "Eternal Eye"; but to break free, the sorcerer exploits people's vulnerabilities, turning them into monsters and creating chaos to escape. Besides the freed evil sorcerer, a deranged billionaire also constantly threatens the ninja. While protecting everyone, Randy must also prevent his ninja identity from being exposed… With the help of his best friend Howard, Randy must defend Norrisville from the evil schemes of the sorcerer, his ally Hannibal McFist, and McFist’s assistant, Viceroy.