John Stevens, a seemingly ordinary college student in Houston, has his life shattered when he discovers he is actually Prince Seelin of the planet Nepton, sent to Earth as an infant to escape galactic conflict. His adoptive parents, Albert and Amber, unknowingly took in an alien child. His past catches up to him with the arrival of Silver-Spike, a robotic assassin, who reveals John's true identity and the impending invasion of Earth by the brutal Demons of the Underworld, led by King Courin. John is rescued by Sear, who, it is later revealed, is Courin's half-Demon son and Prince Seelin's uncle. Sear begins training John to awaken his dormant Neptonian powers, including energy blasts and flight, a process John finds emotionally taxing as he mourns his lost human life.