The Japanese government has devised a new weapon, dubbed the Dimension Tide, in their neverending fight against Godzilla. During a test, the Dimension Tide creates a wormhole through which a giant flying creature arrives and deposits an egg before fleeing again. This egg hatches many flying Meganulas that crave energy to give to their queen, the enormous Megaguirus. Once awaken, the Megaguirus faces off against Godzilla with humans in the middle of the flooded city of Shibuya.
