Adventures of Shintaro the Samurai travelling 18th century Japan with his trusted companion Tombei, battling the enemies of the Shogun and the dreaded Koga Ninjas.
Shintarō saves a young Ainu wrongly accused of murder, relying on his wits and his pistol.
Shintarō captures an escaped thief and takes him to the town of Kiritap to be held until Jinjūrō arrives. However, the villagers' greed allows the thief to free himself and kill one of them and hold another to ransom.
Shintarō comes upon a woman and her young son who are being terrorised by a loan-shark and his offsider, a disreputable but skilled swordsman.
A group of Ainu take a wagon carrying gold from the goldmine on the Shibuchari River in revenge for the death of the son of one of them caused by two of the guards.
A shipwrecked rōnin impersonates Matsudaira Nobuchiyo at the instigation of a smuggler of guns so he can get them to the Ainu who has purchased them.
Shintarō helps a young boy find his mother who was taken by Onibishi, an Ainu chief. Jinjūrō persuades Onibishi to set a trap for Shintarō.
Shintarō, Sanpei and the refugee Ainu women continue on their way to Kunashiri Island. Sanpei mistakenly thinks Shintarō is really after Ainu treasure. Jinjūrō and Onibishi are following them and try to ambush them at Hell Valley.
Goromatsu's two outlaw brothers break him out of Shiranuka Gaol where he is awaiting transfer to Matsumae. He vows to kill Jinjūrō and enlists their help.
Shintarō encounters Tendō Sawanosuke, a blind rōnin and his young daughter who are being harassed by Hidaya's bullies. Sawanosuke is well able to defeat them and Hidaya hires him to kill Shintarō because he has a deed of his. He wants to get Shintarō before Jinjūrō does.
Habaro a young part-Japanese Ainu hunter is persuaded by an ambitious gang leader to kill his boss so he can take over but is shot in turn. Shintarō is accused of the murders but has help from an old friend, a geisha he knew in Edo.
Shintarō helps a brother and sister from Aizu take revenge on the man who killed their father who is now using another name and is the sword instructor for the Matsumae Clan. Jinjūrō plays something of a double game.
Chusuke the Weasel returns to Usu seeking Yaichi, the man who put him in gaol. None of the villagers will stand by Yaichi. They think he should leave town and then maybe Chusuke won't bother them. Yaichi's son worships him and Yaichi fears to disappoint him because deep down he is afraid.
Matsumae government convoys and samurai have been attacked by a man in white who claims to be the onmitsu. Shintarō resolves to unmask the impostor and clear his own name. He calls on Jinjūrō to witness this. Jinjūrō does so but still wants him dead to fulfil his mission.