In 1701, Lord Takuminokami Asano (Yoshizaburo Arashi) has a feud with Lord Kira and he tries to kill Kira in the corridors of the Shogun's palace. The Shogun sentences Lord Asano to commit suppuku and deprives the palace and lands from his clan, but does not punish Lod Kira. Lord Asano's vassals leave the land and his samurais become ronin and want to seek revenge against the dishonor of their Lord. But their leader Kuranosuke Oishi (Chôjûrô Kawarasaki) asks the Shogun to restore the Asano clan with his brother Daigaku Asano. One year later, the Shogun refuses his request and Oishi and forty-six ronin revenge their Lord.
"Genroku Chûshingura" is a Japanese classic movie based on a true story. Kenji Mizoguchi made a too long movie with four hours running time that is actually a slow-paced immersion in an ancient and different culture and code of honor. Unfortunately this beautiful movie is only for very specific Western audiences since it is in Japanese language, shows a different culture, most of the characters are alike (clothing, haircut, biotype) and unusual names that you need to keep in mind. But the movie is worthwhile watching and delights fans of this genre. My vote is seven.
Title (Brazil): "A Vingança dos 47 Ronins" ("The Revenge of the 47 Ronin")