What happens
Clark Kent searches the Andes for missing American engineers and his colleagues Lois Lane and Jimmy Olsen, who have vanished from the Inca palace dungeon. Slipping through the palace, Kent spots what he believes is Jimmy's blond hair among a column of guards marching toward the mysterious valley of the shadows. Inside the mountain, he confronts the captured pilot Bronson, who reveals that the council has sentenced Lois and Jimmy to death. Kent forces open a stone door and meets an old Inca named Seba, who describes a sacred river that vanishes into a hole in the earth and a sacrifice to be made there. Seba refuses to guide him once he is caught in a lie, leaving Kent with little time to reach the valley. This is part eleven of The Adventures of Superman, a transcription serial first broadcast on December 8, 1941.
The Inca palace, its dungeon and tunnels, and the Andes Mountains, including the valley of the shadows.
Characters: Clark Kent, Harry White, Bronson, Jimmy Olsen, Lois Lane, John Craig, Seba
Listen for: Kent's suspicion that the blond guard is Jimmy, and Seba's account of the sacred river and the planned sacrifice.
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.