Two fishing scout pilots make a horrifying discovery when they encounter a second Godzilla alongside a new monster named Anguirus. Without the weapon that killed the original, authorities attempt to lure Godzilla away from the mainland. But Anguirus soon arrives and the two monsters make their way towards Osaka as Japan braces for tragedy.
Mining engineer Shigeru investigates the disappearance and death of his fellow coworkers when prehistoric nymphs are discovered emerging from the mines. After an attack on the local village, Shigeru heads deeper into the mines only to make a more horrifying discovery in the form a prehistoric flying creature. Soon a second monster appears as the two converge in Fukuoka.
In Japan, scientifically advanced invaders from the war-destroyed planet Mysteroid cause an entire village to vanish, then send a giant robot out to storm the city by night, after which they request a small patch of land on Earth and the right to marry earthling women, claiming to be pacifists. Mankind must decide whether to capitulate or to resist.
