In the frigid wilderness of Hokkaido, a group of researchers collaborates with the Self-Defense Forces to look into a series of violent and mysterious animal assaults.

Within an icy cave, they discover a mummified corpse that has been encased for ages in the frozen shadows.

However, upon returning from their expedition, one team member starts to undergo a transformation.

Cells begin to mutate uncontrollably. Flesh tears apart. The human form deteriorates into something completely monstrous.

Humanity has awakened a life-form it was never intended to disturb.