Director Kenji Misumi returns for the fifth instalment of the Lone Wolf and Cub series – Lone Wolf and Cub: Baby Cart in the Land of Demons, Ittō Ogami (once again played by Tomisaburo Wakayama) and his son Daigoro (played once more by Akihiro Tomikawa) are back and this time they are on the “Demon Path in Hell” where they are met by a series of five assassin messengers who represent a clan wanting his services.
Each assassin in turn administers a specific test of Ittō abilities, and upon their defeat give Ittō a partial payment for the job and, as per his usual stipulation, discloses some of the “secrets and reasons” for the killing they wish to hire him for.
By the time Ogami has defeated all the assassin messengers, he learns of a conspiracy to disguise a daimyō’s (feudal lord) illegitimate female offspring as a prince and heir to the clan, while the official offspring, a son, is kept imprisoned and concealed.
A high priest receives a letter concerning this plot and aims to pass this letter to the Shōgun, which would mean the dissolution of the clan, leaving retainers, samurai, and vassals without support. Ittō’s mission is to intercept the priest carrying the letter, kill him and retrieve the letter; the priest will be traveling under the protection of his arch-enemy, Yagyū Retsudō (Minoru Ohki) because the mission just wan’t tough enough alreay!