What happens
Tarzan returns to the camp of the Gregory Safari after searching for Helen Gregory, who has vanished in the jungle. Helen's name was found scratched on a wall in an ancient causeway, and the party follows the old riverbed out of the jungle, after their bearers have deserted them because of a taboo. Tarzan reports that he found no trace of Helen in the jungle, but he does find a well-traveled road leading across rocky ground toward a black volcanic cone called Tu-Em-Baka. Tom, who is seeking the legendary Father of Diamonds said to be hidden in the city inside the crater, plans the next day's march. Later, Tom and Wolf argue over their goals, and Wolf grows openly hostile toward Tom.
The jungle of Oshaka and the rocky, volcanic country beyond it, leading toward the black mountain of Tu-Em-Baka.
Characters: Tarzan, Helen Gregory, Tom, Wolf, Margaret, Donald, Lieutenant Darno, Brian Gregory
Listen for: Tarzan's report that he found no trace of Helen, the discovery of the well-traveled road toward Tu-Em-Baka, and the tense exchange between Tom and Wolf at the end.
Written from the episode itself; it never gives away the ending. Every recording is remastered for the stream: cleaned of rumble, hiss and mains hum (and the old TV whine where we found it), then levelled in two passes to steady broadcast loudness, so one show is never quieter than the next.