Tarzan spurns the love of La, Queen of Opar. When he isn't trying to keep the Bolshevik Rokoff and Clayton (pretender to the Greystoke estate) from reaching Opar, he is attacked simultaneously by two lions, dropped into a pit when a volcano splits the ground, nearly sacrificed by sun worshipers,...
Mary and Bobby Trevor are castaways befriended by Tarzan. When Lord arrives, looking for the family heir, Black John tries to fill that role and marry Mary in England. Tarzan shows up and marries her instead.
After Tarzan's estate is destroyed by Arabs Jane is sold into slavery by a man posing as a friendly scientist. Tarzan develops amnesia after a blow to the head. When he recovers his memory (from a later blow) he defeats the villain, recovers the fabulous jewels of Opar, and rescues Jane.
A seaman on board a sailing ship battles mutinous crew members, a corrupt millionaire trying to take over the ship and falls in love with a girl who turns out to be his adopted sister.
Vacationing in the Canadian Northwest, a playwright and a songwriter both fall in love with Marie Cleste and take her back with them to New York when her father and her sweetheart apparently die in a forest fire. (The father did perish; the sweetheart escaped, crippled, with his blinded Indian...
