Weissmuller starred in six Tarzan movies for MGM with actress Maureen O'Sullivan as Jane and Cheeta the Chimpanzee. The last three also included Johnny Sheffield as Boy. Then, in 1942, Weissmuller went to RKO and starred in six more Tarzan movies with markedly reduced production values. Sheffield also appeared as Boy in the first five features for RKO. Brenda Joyce took over the role of Jane in Weissmuller's last four Tarzan movies (the first two RKO films had not featured Jane).

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