Consumed by negative emotions, Douman is transformed into a giant demon. He now possesses within his body Antenmaru, a demon sealed away over a millennium ago by the desperate efforts of the Ketsuno and Shirino clans. Not even Seimei’s voice can reach to Antenmaru when Gintoki stands before him with his aura-charged wooden sword. How will Gintoki fight the great demon who has returned after a thousand years?!