A delicate balance between the world of demons and humans was disrupted. Karas has been trying to keep the balance, but human arrogance and ignorance kindled in his heart the desire for revenge. Karas changes his name to Eco and becomes the head of a huge army of cybernetically strengthened demons. Few people can stop this armada. But this time, the police officer has another case for concern - an unidentified aquatic monster brutally kills citizens.