What happens
Superman, the reporter Clark Kent, Lois Lane, Jimmy Olsen and Police Commissioner Malone are trapped in a deep concrete tank beneath a hideout in the woods, where the criminal known as the Yellow Mask has kept them. Malone's ankle is badly hurt, and the Mask has demanded the five million dollar jewels in exchange for their freedom. Malone reluctantly calls headquarters and arranges for Captain Sullivan to bring the jewels to the Mask. Kent says he has a plan, but he will not explain it. Meanwhile, two of the Mask's henchmen, Lefty and Joe, stop Sullivan's police car at a crossroads and take the suitcase of jewels for themselves, planning to sell them. This is part 13 of The Adventures of Superman, a 1940 transcribed radio serial.
A concrete tank beneath a hideout in the woods, and a crossroads on the road to the city
Characters: Superman, Clark Kent, Lois Lane, Jimmy Olsen, Commissioner Malone, The Yellow Mask, Captain Sullivan, Lefty
Listen for: Kent's plan for the surprise he says awaits the Yellow Mask, and what Lefty and Joe do with the jewels
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.