There are several reviews here, that stress how the narrative of this chambara film by director Fukasaku Kinji is hard to follow. As someone, who frequently has trouble putting together the plot-lines of 1950's and 1960's jidai-geki films, I did not find this to be the case. Like with so many other samurai films, that were intended for foreign markets as well, this one has a narrator in the beginning, introducing the historical period. I do admit, that the role call happens way too fast, but for the rest of the film, there are a few main characters with clear personalities and agendas, that makes the large narrative comprehensible. Also the pacing is not too fast.
The film's story-line deals with the fight for the shogunate in the 1620's Japan. The second shogun of the Tokugawa line dies under mysterious circumstances without announcing his successor. He has two sons. The older Iemitsu (Matsukata Hiroki) stammers and has a huge birthmark covering half of his face. The younger son Tadanaga (Saigo Teruhiko) does not have these disadvantages, but he also doesn't have a supporter quite as determined as Iemitsu's. That would be the title character Yagyu (Nakamaura Kinnosuke), Iemitsu's fencing instructor, who views the prince as the most important person to him in the whole world, despite having three children of his own. The narrative shows us a fight for power, where innocent blood is shed because of the greed and corruption that takes place amidst the ruling class.
I am not going to spoil it, but people should really stick till the ending, since it powerfully encapsulates the film's message about power corrupting. Before that, the violent images were not clearly used for anti-violence message, since some jidai-geki films merely like to include "cool violence". The presence of Chiba Sonny also makes you anticipate certain things. Chiba's narrative is very important for the final act, but in the early parts, I didn't really like the way it jumped to a different location from the palace drama that we started with.
All in all, this is a very good story, though not historically accurate. There is a big budget, some cameos by famous actors (Tamba Tetsuro, Yamada Isuzu, Mifune Toshiro...), and well-thought-out characters. Especially Nakamura Kinnosuke gives a fantastic performance.
