Fighter D is one of the immortal foot soldiers who survived the failed invasion of Earth thirteen years ago. Ever since, he has been forced to stage ritual defeats every Sunday before cheering crowds for the Dragon Keepers, the sentai heroes who crushed the Villainous Army of Evil. Exhausted by years of public humiliation he treats as nothing but slavery, D disguises himself as a human recruit and infiltrates the Dragon Keepers, training alongside Hibiki Sakurama and Yumeko Suzukiri while working toward the team's destruction from inside.