In ancient times, mighty gods of legend once used their power to shake the very foundation of the earth. Today, their prehistoric foes from Japan's primitive era still fight to safeguard their secrets. Susanoah-oh, the God of Darkness, slumbers in the shadows of the underworld, awaiting his rebirth, but his impending return has not gone unnoticed. Descendants of Japan's earliest inhabitants, members of the Kikuchi Clan, have detected the ominous signs of encroaching darkness. Armed with ancient knowledge and artifacts, they stand ready to confront the God of Darkness. Their challenge is to battle the assembled spirits of the underworld and locate the one young boy destined by fate to harness the deadly might of the gods.