Kaito Yamada

Koichi, now 65, makes a quiet yet defiant choice: he brings his 90-year-old mother—whose days are numbered—home from the care facility to the Satoyama hills of Hitachiomiya, Ibaraki, where she can spend her final summer surrounded by the land that raised them both. As fragile days slip away amid the whispering clear streams and gentle green of northern Ibaraki, buried questions rise like mist: Why did she truly leave? What pain drove her from the child who needed her most?

When the Cosmic Invading Grand Racing Crew, Hashiriyan intends to expand their territory with Earth being their next target to take over, five genius mechanics join forces with an alien machine named Bundorio Bunderas to create their own supercars and special equipment to defend the planet as the Bakuage Sentai Boonboomger!