Zanon's name appears to be derived from the Noble gas element Xenon, which in turn is derived from the Greek term Xenos, meaning 'foreigner'.
An individual Zanon bearing the name of his race appears from deep space piloting a massive spacecraft towards Earth. Earth's resident heroines, the Spacewomen, try to fight against the Zanon, but are easily held back by the ship's crew and Zanon's evil Spacewoman, Giruge. Zanon then reveals his plans to enslave Earth, and in doing so revives the kaiju Gyaos, Zigra, Viras, Jiger, Guiron and Barugon, setting them upon the Japanese islands. The Spacewomen escape, and find a boy with a connection to Gamera, who manages to wake the sleeping turtle. Gamera heads off to fight the other monsters while Zanon commands his pawns from above. After Gamera defeats Zigra, he briefly utilizes a mind-control device on Gamera, making the giant turtle wreak havoc on a dam, but Gamera eventually breaks free after the Spacewomen destroy the mind-control device. After Gamera defeats all of the revived monsters, the Zanon personally fight back, using their spacecraft, but they die after Gamera sacrifices himself to destroy the ship.
- Zanon himself is never actually seen, and his presence is only affirmed by his Spaceship, and from his communications to Giruge.
- The spaceship piloted by Zanon bears a suspicious resemblance to an Imperial Star Destroyer from the Star Wars series of films, and this was most likely a deliberate attempt by Daiei to attract attention and capitalize on the success of the films.
- In a confusing twist, the name Zanon is given to three different things in the movie. It is first used to refer to the alien invading Earth, then used to refer to their ship. Finally, Giruge refers to the kaiju Viras as Zanon, possibly indicating the species inside the ship are the same species as Viras. However, since they are not seen outside the ship, the point is debatable.
|Aliens||Mysterians • Pairans • Xiliens • Kilaaks • Yog • M Space Hunter Nebula Aliens • Seatopians • Black Hole Planet 3 Aliens • Futurians • Millennians • Natarls • Vortaak • Atlanteans • Tachyons • Terrans • Virasians • Spacewomen • Zanon • Flashers • Garogas • Cryogs • Devonians|