This is one of those movies that have an all Japanese motivation. A girl is trained from childhood to avenge the death of her father and the brutal rape of her mother. Then she does it. Lots of blood and lots of sword fighting. Well, she does most of it, everybody else pretty much dies.
The movie is well done, although I think it is hard to watch for most of the people nowadays, since it has that 60's-70's feel to it. I can see how this could have been an inspiration for Kill Bill. If you liked Kill Bill for other reasons than that it had Uma Thurman and Lucy Liu in it, then you will love this film.
If you watch the movie, you will probably have fun, but if you look at the whole picture (pun intended) there isn't much to it other than the actual revenge and death of everyone. The girl is very nice, the acting is OK, the atmosphere, settings and soundtrack are good, but that's all. No strange twists of the story, nothing unexpected.