During a border ambush, Lord William abandons his wife Isabella to rescue his beloved Bianca, leaving Isabella to tumble down a slope and suffer a miscarriage. Showing no remorse, William blatantly favors Bianca, harshly mistreating the recovering Isabella and even seizing her personal study for Bianca’s use. Bianca then forges treason letters to frame Isabella, who is stripped of her title and thrown into the dungeon. Isabella secretly turns to her family, House Lancaster, for help.