In a St. Augustine, Florida resort hotel, heiress Lillian Travers discovers her fiancé, Dr. Fred Cassadene, in the arms of another woman. Angry and jealous, Lillian swallows a seed that she found in an antique box from Africa that, an accompanying note claims, came from the Tree of Sexual Change and will end a woman's suffering. She instantly becomes a man and, although still clad in women's clothing, flirts outrageously with the female inhabitants of the hotel. Lillian next gives a seed to Jane, her mulatto maid, who then becomes a lust-filled valet. Eventually, Lillian assumes a male identity. But after Fred believes that "she" has been murdered by the man she has become, Lillian tries to prove to Fred that she is indeed Lillian. She then gives him a seed and he turns into a woman. Still dressed as a man, he chases after his male acquaintances, then, after stealing a dress, jumps into the ocean. As he drowns, Lillian awakens to discover that she has been dreaming and that Fred has just come to call.