Two men, tired from work, visit the town of Chichibu to enjoy their favorite hobby - exploring caves. But little do they know, the town has been secretly protected by the descendants of the righteous Shinobi ninja since the Sengoku period. The two unlucky friends accidentally break a spell that awakens two colossal beasts, Jaron and Goura. The area’s rival clans manipulate them into a fierce battle, bringing chaos to the area. But a righteous female ninja steps up, wanting to stop the destruction and restore the seal. Can she defeat the evil ninjas that stand in her way before Chichibu is completely destroyed by two kaiju?

The giant monster Raiga returns, rising in Atami Harbor and attacking the city. A second kaiju, Ohga, soon joins the chaos, and the two monsters clash, destroying large sections of the city. Defense forces launch two new weapons, the giant tank Kamikaze and the drill tank Gokumei, to meet the the monster invasion head on. But as the beasts work their way to Tokyo, will they be enough to stop the monsters from laying waste to the city?