A mass jailbreak occurs on a vast maximum-security prison planet. In the thick of the ensuing riot, nine stranded Legionnaires struggle to survive against thousands of the most dangerous criminals in the galaxy.

The Legion is called in to Planet Hell, a penitentiary located in the middle of the sun that has recently lost main life support. The team will have to work fast and in uncomfortable conditions to ensure the facility can be brought back online before everyone slowly cooks to death. The Legion's rival, the Workforce, is also dispatched to try and beat the Legionnaires to the task. Unfortunately, the heroes don't count on their contact, the warden Bur Rac, turning on both teams and unleashing all the prisoners on Planet Hell.