I have to wonder what it is like for those who have not read the manga epic "Lone Wolf and Cub" by Kazuo Koike and Goseki Kojima when they watch these movie adaptations from the 1970s. Those of us who read all 142 episodes have the advantage of recognizing the various stories along the Assassin's Road that Koike works into each script. Consequently we are perfectly content to enjoy the episodic nature of these films, whereas the uninitiated might be bothered by the lack of a plot, especially if they have seen the first two films in the series and are expecting the Yagyu to be more of a presence.
"Kozure Ôkami: Shinikazeni mukau ubaguruma" ("Lone Wolf and Cub: Baby Cart to Hades") is the third of the six films starring Tomisaburo Wakayama as the assassin for hire and Akihiro Tomikawa as his cub. Father and son continue along the Assassin's Road and there are three episodes from the manga that constitute major sections of the film, along with brief moments culled from other stories (e.g., the river crossing from #53 "Drifting Shadows" and using Daigoro drowning in a river to set up a kill from #2 "A Father Knows His Child's Heart as Only a Child Can Know His Father's"). In fact, when you spot something that does not seem familiar from the manga, it will send you scurrying to your Dark Horse Comics collection to see if you have simply forgotten it.
The first major section is from "Wandering Samurai" (#46), where a mother and daughter are brutally raped by a group of "Watari-kashi," who murder their escort. When Magomura Kanbei (Go Kato) shows up and see what has happened he kills the women and then makes the assailants draw lots so that he can kill one of them, who will then be blamed for the atrocity. However, Ogami Itto has seen what has happened and the best moment in this film comes AFTER the inevitable duel between our hero and Kanbei, which involves a philosophical discussion on the true way of the warrior.
We move directly to the second major section, which adapted "The Virgin and the Whore" (#18). A young peasant woman who has been sold into prostitution kills her pimp when he tries to take advantage of her. Lone Wolf and Cub are staying at the same inn and when she tries to hide in their room, she comes under Ogami Itto's protection. The "Boohachimono" that run the brothel want to punish her, but our hero refuses to allow it and agrees to take her place instead when their leader, Torizo (Yuko Hamada), demands satisfaction. He is then subjected to the punishment of being repeatedly dunked upside down in a tub of water and then being beaten black and blue by bamboo sticks. As a result the young girl is given her freedom.
This becomes a set up for the big fight at the end, as Torizo sets up Ogami Itto with an Elder who wants to hire the assassin Lone Wolf. Unfortunately our hero has a prior commitment, which requires the assembling of dozens of samurai and other warriors to try and take down Lone Wolf and Cub. The set up is slightly different, but the battle is essentially what we have in "The Yagyu Letter" (#50). This has to be the climax for the film because you can count the number of people still alive in the film on the fingers of one hand.
By this point Wakayama has the part down well past the point of cold. His face makes Buster Keaton look like Jim Carey. Add to this how the choreography for the sword fights is well above average for this genre and you can see its appeal to fans. True to the manga, there are several instances of nudity and blood spurting (but much more of the latter). What is missing is the sense of Ogami Itto's mission, which was set up in the first film in the series. This time around Lone Wolf is killing a lot more people to stay alive and to right wrongs than he is to make another 500 ryo. But then we had no clue at that point what those accumulated fees were for. Keep in mind that these first four movies were made in 1972, which was only two years after the first story of "Kozure Ôkami" was published.
I know these movies were edited and dubbed into "Shogun Assassin" in 1980, but just take the high road and avoid that butchery in favor of the original sextet of films: (1) "Kozure Ôkami: Kowokashi udekashi tsukamatsuru" ("Lone Wolf and Cub: Sword of Vengeance," 1972); (2) "Kozure Ôkami: Sanzu no kawa no ubaguruma" ("Lone Wolf and Cub: Baby Cart at the River Styx," 1972); (3) "Kozure Ôkami: Shinikazeni mukau ubaguruma" ("Lone Wolf and Cub: Baby Cart to Hades," 1972); (4) "Kozure Ôkami: Oya no kokoro ko no kokoro" ("Lone Wolf and Cub: In Peril," 1972); (5) "Kozure Ôkami: Meifumando" ("Lone Wolf and Cub: Baby Cart in Land of Demons," 1973); and (6) "Kozure Ôkami: Jigoku e ikuzo! Daigoro" ("Lone Wolf and Cub: White Heaven in Hell," 1974). The above does not include literal translations of each Japanese title but rather the name given their most recent U.S. releases (I believe the original U.S. releases in the 1970s just numbered these as "Swords of Vengeance" I-VI). The literal translation of this third film in the series would be "Lone Wolf and Cub: Perambulator Against the Winds of Death," so you can see why that would not be the way to go.