For centuries, the magic and human worlds have been at peace with each other, though physically seperated by a magical gate. But when the powerful magic spheres are stolen and fall to the Earth below, the king of magic sends Boss, a fighter; Lime, a master transformer; and Poogie, a master morpher to retrieve them. With not much time, the trio must retrieve the spheres which, when in contact with the human world, suck up the negative emotions of household objects and become BEMs, Bug Eyed Monsters!

Everybody goes to the ocean for a summer festival and the guys sneak off to a cursed island.

Nuclear testing has resulted in the abrupt evolution of the Fumoon, a tiny but highly intelligent humanoid race on a small island, who are detected by Dr. Yamadano. Except for a few witnesses including the detective Shinsaku Ban, and the young men Rock and Kenichi and Kenichi’s sister Pichi (Pinoko), no one believes him. The Fumoon are kidnapping animals from around the world to bring with them as they use their space ships to evacuate the earth, because they know Earth is shortly to be destroyed by an enveloping cloud of black gas created by a stellar explosion. The Fumoon intend to abandon mankind, but one Fumoon, Rokoko, who becomes good friends with Kenichi, tries to help Dr. Yamadano and the others to develop a space ship to allow a few humans to escape, with the help of Dr. Ochanomizu and Dr. Frankenstein.

In the Fifth Year of the Keicho era, the Tokugawa clan sought to solidify their control of Japan. Hidetada Tokugawa has come to the doorsteps of Ueda Castle with the intentions of having the Sanada clan open its doors to him. But the Sanada and their retainers have other plans...