In feudal Japan, during a bloody war between clans, two cowardly and greedy peasants, soldiers of a defeated army, stumble upon a mysterious man who guides them to a fortress hidden in the mountains.
Shipwreck survivors found on the presumably uninhabited Infant Island leads to a scientific expedition that discovers a surviving native population along with the Shobijin, tiny twin fairy priestesses of the island's mythical deity called Mothra. After the fairies are kidnapped by an exploitative businessman named Clark Nelson, Mothra sets out to rescue them.
In the not-too-distant future, the Earth finds itself constantly under attack from extraterrestrial threats. The Terrestrial Defense Force establishes the Ultra Garrison, a team of six elite members who utilize high-tech vehicles and weaponry. Joining their fight is the mysterious Dan Moroboshi, secretly an alien from the Land of Light in Nebula M-78, who transforms into his true form in times of crisis, Ultraseven.
