chunk: He, the two lovers and the lion are soon reunited, but attacked by warriors from the lost city of Xuja, hidden in a secret desert valley. Tarzan is left for dead and Bertha and Smith-Oldwick taken prisoner. The Xujans are masters of the local lions and worshippers of parrots and monkeys. They are also completely insane as a consequence of long inbreeding. Recovering, Tarzan once more comes to the rescue of his companions, aided by the lion he had saved earlier. But the Xujans pursue them and they turn at bay to make one last stand. The day is saved by a search party from Smith-Oldwick's unit, who turn the tide.
  Afterward, Tarzan and Smith-Oldwick find out that Bertha is a double agent who has actually been working for the British. Tarzan also learns from the diary of the deceased Fritz Schneider that Jane might still be alive.