During World War I, westerner Cheyenne Harry is a horse seller, but he refuses to part with his favorite horse and friend, Cactus. One night, broke and drunk, he sells Cactus to an Englishman for $350 which he soon loses gambling. When Harry discovers that Cactus is being sent to the war in France and probable death, he gets a horse- tending job on the ship. When they get the opportunity Harry jumps off the ship with Cactus and they swim to shore. Harry is eventually caught but is allowed to work off his debt and keep Cactus.
While attending college in Washington, D.C., Yuki Onda, the daughter of a Japanese samurai, meets and falls in love with Pierre Le Beau, a diplomatic attaché. At the outbreak of the Russo-Japanese War, Pierre is sent to Japan as attaché to the Australian ambassador. When Yuki's father discovers his daughter's romance with a foreigner, he becomes enraged and betroths her to Prince Hagane for political reasons.
Failing to hear from her brother Jimmy after his departure for the Klondike, Barbara Henderson goes in search of him. Arriving in the frozen North, Barbara learns that her brother has been murdered and vows vengeance.
