Kiryu Mamoru, a subordinate boss of the Tomogashira Group, earns a living through the shady business of "yamikin" or underground lending. He preys on desperate customers who cannot get loans from legitimate lenders, charging exorbitant interest rates of 30% in 10 days or even 90% in some cases, in violation of the law. With the backing of his yakuza group, he employs extremely vicious and unethical methods...

A talented but troubled Edo Period swordsman, Kanemi Sanzaemon. Three years earlier, Kanemi killed a woman, Renko, the corrupt mistress of the powerful daimyo Tabu Ukyou. Unexpectedly, Kanemi received a lenient sentence for his crime and is allowed to return to his clan after only one year of imprisonment. Following his return, Kanemi is faced with the death of his wife, Mutsue. Thereafter, Kanemi lives with and cares for his wife's niece, Satoo, who has secret affections for Kanemi and expresses them by helping change his bleak outlook on life. Meanwhile, Kanemi's develops his unique "bird-catching" sword technique which he will soon put to test in battle for the first time against the fearsome swordsman, Hayatonosho Obiya.