Lex Barker plays the Lord of the Jungle in . Against his better judgment, Tarzan agrees to guide British government agents Edwards (Patric Knowles) and Rokov (Charles Korvin) into the land of the Wazuri Tribe, ostensibly to harvest uncut diamonds for national-defense purposes. In reality, Edwards and Rokov are a pair of criminals who intend to use the gems for their own nefarious purposes. Dorothy Hart co-stars as Jane, while Tommy Carlton plays a substitute for Tarzan's adopted son "Boy." The film's best scene takes place just after the opening credits, as Tarzan rescues Carlton from a deadly tribal ritual. was co-written by Cyril Hume, who'd contributed mightily to the "Tarzan" series back in its big-budget MGM days.