Castle Menagerie, number twelve in Daiei Studio's Kyoshiro Nemuri/Sleepy Eyes of Death/ Son of the Black Mass series is another good one. This entry has a more interesting plot than usual for the series. It is also a fitting series end for actor Ichikawa Raizo.
This one concerns the women in the Shogun's harem. Although all in the same bed so to speak, the women are very much dedicated to their clans. Two opposing groups have sprung up in the harem, each trying to catch favor by having one of their members produce the shogun's first (male) heir. The leader of one group is Nishiki Koji, a cunning, evil woman who ranks second in the series's line of villainess (only Princess Kiku from the fourth and seventh entries is nastier). The plot has more than just that strand. Christians are being persecuted. Ninjas are being sent to kill Kyoshiro Nemuri. There is the usual clan manipulation. Finally, and most intriguingly, there is another person calling himself Kyoshiro Nemuri running around killing men, raping women, and drawing attention to the real Nemuri. All of these plot threads tie together nicely by the end.
In addition, this twelfth entry features a few unusual, but effective, scenes. The oddest is when Nemuri is approached in his bed chambers by a group of masked dancers who want him to bring to life a mask by sleeping with the woman wearing it. In spite of the nightmarish quality, the scene is not a dream.
I also wanted to mention the finale. At the climax, Kyoshiro Nemuri finally faces off with the imposter. The duel is in a forest during autumn. The colors are bright and the swordplay is exceptional. After the duel is finished, Nemuri walks away through this forest in the process of dying for the season. It is a fitting last shot for Ichikawa Raizo's Kyoshiro Nemuri. Raizo died of cancer the year Castle Menagerie was released (1969).
Daiei Studio wanted to continue with the series, so Hiroki Matsukata was hired to replace Raizo for two more films. After that, the series was taken to television with different actors playing the role. However, that may be more Kyoshiro Nemuri than I want at the moment. I will watch the two Matsukata movies though. I am curious about Matsukata but also doubtful. Raizo owned the role of Kyoshiro Nemuri.