This is a japanese movie starring Kiichi Nakai and Koichi Sato. It's called Mibu Gishi Den in Japanese.
It starts off in Meiji era Japan and with an old man taking his grandson to a doctor. A photograph at the doctor's place triggers his memories. Between his and the doctor's recollections, we hear the story of Yoshimura Kanichiro.
Much of the story that is told is set in an interesting period of Japanese history, called Bakumatsu (1853-1869). After 1600 CE, when Tokugawa Ieyasu became the unquestioned Shogun (military overlord) of Japan, the succeeding Tokugawa shoguns became increasingly insular and froze Japan in time, strictly ordering the society and controlling the access to foreign trade. They managed to rule unopposed for the next 250 years. So, when the American Commodore Matthew Perry came with his warships in 1853 to force them to open ports for trade, the Japanese simply did not have the technology to resist. This caused a major upheaval in Japanese society and led to the overthrow of the Shogunate and the establishment of the emperor as the sole titular head of Japan.
Obviously the Shoguns did not go away quietly, and there was a lot of bloodshed. There were pro and anti-Shogunate militias who fought each other. There were a lot of political assasinations. This period threw up some very interesting characters, one of who were the Shinsengumi, a pro-Shogun militia. The Shinsengumi had quite a few strong and famous swordsmen among their number. The Shinsengumi are respected even now as tragic heros and are admired for their fortitude and courage. The Shinsengumi had strict rules for its members, hard training and a hard selection process. If any rules were broken, the offender was ordered to commit seppuku.
Saito Hajime was one of their leaders. He was one of the few of the Shinsengumi to actually survive the period, and went on to become a police officer in modern Japan.
The old man in the beginning of the picture is Saito Hajime. It is this militia that Yoshimura joins.
The doctor and Saito Hajime obviously have different views and different pieces of the story, but the movie stitches these narratives together very nicely. I found it a touch too melodramatic at some places, but it does not detract from the movie.
The sword fights are just awesome. Quite fast and very furious :)
I liked all the characters, but especially Saito Hajime. Koichi Sato played him with cool aplomb. He initially comes across as a cold-hearted murderer but by the end of the movie, I found myself cheering for him. He is just way too cool in a sardonic, the-only-reason-I-am-not-killing-everyone-around-me-is-because-I-don't-feel-like-it-right-now kind of way :-)
Another aspect I really liked was the way the friendships between different characters were portrayed.
This movie reminded me a lot of Twilight Samurai. They are both set in the same time-period, deal with very similar issues (following one's duty, common people being compelled by the ebb and flow of history etc) and the storytelling styles are also quite similar.
In all, I highly recommend it.