Beautiful space alien princess Lum invades Earth on her UFO, and unlucky Ataru Moroboshi's world gets turned upside down! Will Lum become Earth's electrifying new leader? Or will Ataru somehow miraculously save Earth from space alien onslaught?

There's never a dull moment on the beach in summer, especially when Ataru and Mendo encounter a beautiful woman looking for her lost child on the bottom of the ocean. Could this be Ryunosuke's missing mother? Later, Ataru and Ten's ongoing battle for dominance creates some serious collateral damage when Lum gets hit point-blank with a projectile rice cooker. Will she ever talk to them again?!