What happens
Clark Kent and Jimmy Olsen are aboard a steamship bound from Panama to the United States, carrying a cargo of nitrate. After Jimmy hears Morse code coming from a cabin, Kent and Dr. Barrington search for him. The episode is part six of the Superman serial The Nitrate Shipment, which aired on May 2, 1941. Kent calls a meeting of the passengers, but the search for Jimmy grows urgent as the mysterious messages continue.
A steamship travelling from Panama to the United States
Characters: Clark Kent, Jimmy Olsen, Pat Flanagan, June Barrington, Dr. Barrington
Listen for: Jimmy hearing Morse code from a cabin and then disappearing
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.