Azumi is a Japanese movie that takes place during the Tokugawa era. A samurai is told to take a band of kids orphaned by the war and to raise them as assassins to destroy Toyotomi and the other warlords to prevent another war. Azumi (Aya Ueto) is the only girl in the band of assassins. She was found as a small girl by Nachi (Shun Oguri ^.^) and taken in by their master.
The 10 (Azumi, Nachi, Ukiha, Hyuga, Amagi, Nagara, Yura, Awa, Hiei, and Komoru) grow up as brothers and sister. One day their master finally says it's time to leave their secluded hut in the mountains and go on the "mission" they had been trained for their entire lives, but first he has one more thing to teach them. In order to make sure the teenage assassins have no emotions on who they kill, they are ordered to pair up... then kill the other.
The movie is amazing on action, BUT, if you are looking for as-real-as-it-gets effects you won't get it. Azumi's style is artistic violence, so to speak. Larger blood splatters, but not "gory". Aya Ueto portrays her roll perfectly. Azumi is NOT a cold blooded killer, but she does her "mission" and still carries the burdens of her friends and the victims with her, making her an emotional turmoil on the inside and a sleek, sword-wielding assassin on the outside.
There is also an Azumi 2 out, which is also fantastic. I suggest watching them both. ^.^