This historical epic dramatizes the Battle of Peking, a turning point of the Boxer Rebellion in China in 1900. When Dowager Empress Tzu-Hsi (Flora Robson) orders the Boxers, a group of Chinese secret societies, to massacre foreigners within China, a group of ambassadors, their families and staff hole up in a diplomatic compound. Major Matt Lewis of the United States Marine Corps (Charlton Heston) leads the defense while romancing Russian baroness Natalie Ivanoff (Ava Gardner).