A lost society in the jungle has been kidnapping women in the hope they will be able to repopulate, as a mysterious disease is killing them off. When Jane and a doctor's nurse are kidnapped by them, Tarzan leads an expedition into the jungle to rescue the women.
With Johnny Weissmuller consigned to Jungle Jim films, Lex Barker took over the role of Tarzan in the RKO series. This is the first of the series I've seen with him in the lead, though it was actually the second of the five films he made as the character. The series does appear to have regained some of its savagery, due no doubt to a combination of the facts that a younger Tarzan was in much better shape for the action sequences, the departure of Boy had dedomesticized the series a little, and the erosion of the Motion Picture Code as beginning to show. There are some nasty scenes here, including a man's face being cut and an elephant stepping on a man's arm. Barker doesn't seem quite at ease with Tarzan's fractured English, but he's lithe, athletic and moves like an animal. The story itself is pretty ordinary, and Cheeta's antics are forgettable. Still, the movie really comes to life in the middle of the movie, when Tarzan encounters a tribe of killers who disguise themselves as bushes; there's something genuinely unsettling about these natives that adds a sense of horror to the proceedings, which, along with the lost civilization, supply the fantastic aspects of this Tarzan opus. It should be interesting to see some of Barker's other forays into the character.