The story is set in a futuristic and peaceful world made possible thanks to the invention of the Manifestation Engine (示現エンジン Jigen Enjin), a powerful engine that creates energy from the sky and helped to prevent an energy crisis five years prior.
On the island of Izu Ōshima, Akane Isshiki lives a peaceful life with her family. When the world is threatened by an alien force known as the Alone, Akane is given a special key by her grandfather, Kenjirou, which allows her to access the Vivid System and wear a Pallet Suit, granting her special powers. Joined by her friends Aoi, Wakaba and Himawari, Akane fights to protect the world from the Alone.