The three brothers discover that the human experiment banned after destroying the "Orochi", is still going on to secretly revive the evil snake. They also find out that some ex-members of the Yamainu (the Japanese military unit formed to kill the snake) are behind this conspiracy. The brothers fight together again in a battle against the military.
One year has passed after the great battle against the Orochi (gigantic snake). Tenka Kumo had been paralyzed from the final battle and he took part of the government’s human experiment before the battle. Tenka withdrew himself from society but his younger brothers Soramaru and Chutaro find out the secret past about their older brother.
As an unexpected typhoon bears down on a small tropical island, a group of students trapped at school find themselves forced to put aside their personal issues and work together. Not only to save themselves, but possibly the lives of everyone on the planet!
