Invasion of Astro-Monster

Two astronauts, Fuji and Glenn, are sent to investigate the surface of the mysterious "Planet X" There they encounter advanced and seemingly benevolent human-like beings called the Xiliens and their leader the Controller. The aliens usher the astronauts into their underground base, and moments later the surface is attacked by a creature called "Monster Zero" The astronauts are given a tape with instructions for the miracle cure and sent home, leaving Godzilla and Rodan behind. Glenn and Fuji arrive to share the Xilien's weakness.