When Lord Murashige rises up against the tyrannical Oda, he finds himself besieged within the walls of his own castle. Isolated, he is confronted with a series of mysterious crimes that shatter the fragile order of his court, plunging the fortress into fear and suspicion. With Oda's army closing in and a traitor hiding among his ranks, Murashige is forced into an uneasy alliance with Kanbei, a brilliant and dangerous strategist held prisoner in the dungeon, as he must outwit his enemies and uncover the truth before time runs out.