Lone Wolf and Cub: Baby Cart in Peril (1972)

The fourth Lone Wolf and Cub film got a new director (Buichi Saitô), who brought a subtly different approach, making it more emotional than previous entries. Thematically it tackles the parent/child relationship from a number of perspectives, not just through Ogami Ittō and his son Daigoro.
Saitô also added more female nudity and because of that it's sometimes criticised as being 'lowbrow'. No doubt the occasional topless kills will appeal to a certain subset of viewers, but if you've followed the series from the beginning and noticed the progressive role of women, then you'll see past that easily. Collectively the exploitative scenes serve a purpose other than mere titillation; they have a genuine (dramatic) role to play in the bigger picture, one that becomes clear as the story nears its end.

3½ distant echoes out of 5