Giant monsters, including Rodan, Gigan and Mothra, are wreaking havoc around the world. Suddenly, a UFO appears and causes the monsters to vanish. Aboard the spaceship are Xilians, extraterrestrials who wants to help the human race defend itself from Gorath, a rogue planet on a collision course with Earth. M Organization soldier Shin'ich Ozaki (Masahiro Matsuoka), biologist Miyuki Otonashi (Rei Kikukawa) and her TV reporter sister Anna (Maki Mizuno) soon determine Gorath's a hologram and the Xilians are evil aliens who intend to conquer the Earth. Exposed, the Xilians unleash the monsters to destroy the planet. Racing to the South Pole, Captain Gordon (Don Frye) frees Godzilla, mankind's only hope to defeat the monsters and save the Earth.