A graphic novel version of the most dramatic example of bushido—the samurai code—in Japanese history.      In the eighteenth century, forty-seven samurai avenged the death of their master in a plot that would take over two years to complete. After succeeding in their mission, the masterless samurai—known as ronin—all committed ritual suicide. The story, which is a national legend, remains the most potent example of Japan's deeply rooted cultural imperative of honor, persistence, loyalty, and sacrifice.     The historical event has inspired many writers and artists over the years and numerous fictionalized versions and adaptations have emerged. In The 47 Ronin, Sean Michael Wilson has created a historically factual portrait, enhanced by evocative and often lyrical drawings by Akiko Shimojima. While there are other depictions of the story in manga form, this version stands out as being the most accurate and most compelling. Wilson and Shimojima have made the characters nuanced and relatable.