A truce has been established between the world and hell since ancient times. As long as the contract is not exceeded, the demons of hell cannot cause trouble. For thousands of years, the two worlds have been peaceful. However, in hell, a long-simmering evil force is quietly ready to launch... Prince Nuada (Luke Goss), the tyrant who can walk in both worlds of heaven and earth, attempts to awaken the invincible army of Warcraft with blood and burn the world with the fire of hell. Under the call of his blood, the magical beasts that had been dormant for a long time in the depths of hell rushed out of the underground. Facing the invincible Golden Army, the only one who can save the world from falling into purgatory is Hellboy (Ron Perlman). Although he had the blood of the devil flowing in his body, he had long converted to the good Red-Horned Satan and stepped forward to stand on the side of mankind. He will work with allies of the Paranormal Research and Development Bureau such as the Flame Woman (Selma Blair) and Murman (Doug Jones) to kill demons across the Yin and Yang realms and resist the catastrophe on earth! Will the baron be swallowed by his evil nature again this time?