A helicopter flying over Foret Town is attacked by a mysterious monster. The only survivor is an amnesiac who was sealed in a metal crate. After being ambushed by monsters on the town's outskirts, he discovers that he can transform into a powerful werewolf. He continues on to discover who he is, and why he was sent to Foret Town.

When players control as Luke, they are not very strong. But he is able to transform into a werewolf, which can perform high jumps in addition to becoming incredibly powerful. Fighting monsters will give Luke DNA data that will allow him to upgrade his beast attacks for more powerful combos. More beast forms can be discovered, each with their own special powers to overcome previously impassable obstacles.