Hamaru, a butcher working at a livestock company, is invited by his boss to go on a business trip to Japan. However, he soon discovers that the place he has been sent to is a criminal organization run by the Yakuza. In order to survive in this dangerous environment, Hamaru struggles and gradually awakens his hidden talent for using knives. Hamaru, the butcher who has now set foot in the underworld, challenges the pinnacle of the criminal world to stay alive.