When Dazai and Chuuya were forced to work together against a mysterious gifted that was threatening to destroy the Mafia and the Gifted Organization, they were engulfed by a blanket of darkness that the gifted released from his hands. When they woke up they were in a completely different place, where they realise that they have become their sixteen-year-old-selves, and needed to enroll into a school of heroes to figure out how to return to their world.