会津松平藩的武士笹原伊三郎（田村正和 饰）以上门女婿身分入赘妻家，和妻子（梶芽衣子 饰）相敬如宾，儿子与五郎（绪方直人 饰）耿直孝顺。这一日，会津藩侧用人高桥外记（北村有起哉 饰）突然带来一则惊人消息，因藩主（大杉涟 饰）宠幸之侧室阿市（仲间由纪惠 饰）惹出纷争，而被藩主一怒逐出，并命令下嫁笹原家。左右为难的伊三郎无奈承命，幸运的是温柔美丽的阿市很快习惯笹原家的生活，且与丈夫、公婆相处融洽。谁知好景不长，阿市与藩主所生之子成为继承人，作为生母的她面临被召回的命运。为了保护儿子、儿媳的幸福，伊三郎公然抗命，为此他不得不对抗全藩，跟被迫和挚友浅野带刀（松平健 饰）刀剑相向……

　　本片根据泷口康彦的原作改编。

In the Edo period of Japan, a samurai’s life belonged to his lord. On the battlefield or in the home, a loyal samurai must always obey his lord’s commands. This is the tragic story of one such loyal samurai, whose love for his family forced him to make the ultimate choice of disobeying the wishes of his lord.