Tarzan and the Madman is a novel by American writer Edgar Rice Burroughs, the twenty-third in his series of twenty-four books about the title character Tarzan.

Written from January to February 1940, the story was never published in Burroughs' lifetime.

The man is under the delusion that he is Tarzan, and he is living in a lost city inhabited by people descended from early Portuguese explorers.

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