Shinichi “Sonny” Chiba returns as the reckless son of a private detective takes on the case of a minor league baseball pitcher who disappears right before signing a contract into the major leagues. Meanwhile, the body of an orthopedist is discovered in the river.

The tyrannical Lord Danjo Mikoshiba covets the rich, fertile lands surrounding Lake Yakumo. During a memorial ceremony for the late Chigusa lord, Mikoshiba launches an attack, overthrowing the honorable Lord Juro. Just when all seems lost, Daimajin rises from Lake Yakumo to settle a score of his own.