What happens
Clark Kent and young Jimmy Olsen pursue the connection between Professor Hagen, an animal trainer with the L'Oubeck Circus, and a series of crashes involving planes of the National Air Service. Hagen has been preparing a deadly device in a mountain cabin, aimed at a new aircraft due to reach Bridger Field at midnight. Jimmy and Ed Hamlin ride mules up the narrow trails toward the cabin, racing against the clock as a rockslide threatens their path. Superman appears to intervene, and the story follows the tense final minutes before the arrival of the mystery plane. The episode is the sixth part of the Adventures of Superman serial, first heard on May 10, 1940.
Bridger Field and the Rocky Mountain trails above it, near L'Oubeck Circus, late at night
Characters: Clark Kent, Superman, Jimmy Olsen, Professor Hagen, Ed Hamlin, Carl
Listen for: The rockslide on the mountain trail and Superman's rescue of Jimmy and Ed Hamlin beneath it
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.