Godzilla Vs. Megalon (1973) - (Movie Clip) I Will Unleash Megalon!
Were suddenly inside subterranean Seatopia (probably beneath Easter Island) where the boss guy (Robert Dunham) has gotten the green light from agents on earth to loose the (title) monster theyve been keeping stashed, after nuclear tests messed up their kingdom, in Godzilla Vs. Megalon, 1973.