Superman confronts the alien entity known as the Passenger while battling Mongul's forces on Warworld, with Supergirl and Aquaman aiding in a desperate effort to prevent a galactic war. Meanwhile, Jon Kent uncovers a hidden threat tied to Krypto's origins, forcing Lois Lane and Vulko to navigate political tensions among the Legion of Super-Heroes. The clash between Superman and the Passenger escalates, revealing a connection to Earth's past that could alter the future of the DC Universe.