On an idyllic vacation island in the southern seas, a young couple is trying to overcome the death of their only son. But for Seiichi Kirishima, the husband, the trip has a different purpose altogether. He plans to kill his wife and dispose of her body deep inside the forest. However, when his plan goes awry and his wife manages to escape, Seiichi follows her into a dark cave, only to find himself trapped inside and soon hunted by a savage creature with an insatiable hunger for human flesh...