Samurai Isaburo Sasahara (Toshirô Mifune) faces the wrath of his clan when he exhibits disobedience in favor of what is right. When the ruling lord forces his son, Ichi (Gô Katô), and his unwanted mistress (Yoko Tsukasa) into marriage, the two fall in love despite all expectations. However, when the callous ruler requests Ichi's return only two years later, Sasahara, unwilling to see his son and daughter-in-law torn apart, is prepared to fight for their union.