What happens
Tarzan joins Tom Gregory's safari on its search for the forbidden city of Asher, where Tom seeks a diamond and Tarzan hopes to find Helen Gregory's brother, Brian. Helen vanishes from camp at night, and Tarzan sets off alone into the jungle to find her, leaving the safari to press on toward Tuenbaka. Days pass without word, and the party's hopes begin to fade. When Larsen disappears into a hole in the ground, the others descend and discover an ancient stone stairway and causeway beneath the jungle, marked with carved writing that the group sets out to examine.
The jungle near Tuenbaka, on the route toward the forbidden city of Asher, including the safari camp and an underground stone passage.
Characters: Tarzan, Tom, Helen Gregory, Margaret, Larsen, Wolf, Donald, Monsieur Dupree
Listen for: Tarzan's departure into the trees to search for Helen, and the discovery of the stone stairway and writing beneath the jungle floor.
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.