Mothra has fallen after a fearsome battle with a terrifying new kaiju, Antra. Without its protector, the world has entered into a state of desolation. Kaiju roam freely, and what remains of humankind has been forced into hiding.But all hope is not lost! Mira is a young woman living in the wasteland, who believes she lost her entire family in Mothra's final stand. That is, until her missing twin shows up at her door with two fairies! If her sister is to be believed, Mira might hold the key to the rebirth of Mothra and the Earth's return to normalcy. They just have to travel back in time and get its egg from the Jurassic period first.