An expedition in the South Pacific lands on a tropical island where the natives worship the mysterious deity Gappa. An earthquake opens up an underground cavern and a baby reptile is discovered inside. The natives warn the foreigners to leave the hatching alone, but they do not listen and take it back to a zoo in Japan. Soon after, mama and papa Gappa start smashing Tokyo looking for their kidnapped child.
Gappa the Triphibian Monster
Magazine reporters transport a monster child, freshly hatched from an Obelisk island egg, back to Japan.