What happens
Jerry and Joan are aboard a Euclidean submarine, en route to help capture Johnson and the Gregory rescue boat. Captain Bradford and Mrs. Gregory have been left aboard the captive yacht inside a submarine lock on the Magic Island. After hearing Jerry's radio message urging Johnson to bring his boat to the island, they suspect Jerry is being forced to send it. Water then rushes into the lock, and the captain and Mrs. Gregory flee onto the rock ledge, unsure whether the lock gate has broken. The captain's exchanges with the skipper and the Euclidean G-47 suggest the flooding was deliberate. Meanwhile, the submarine's commander keeps Jerry and Joan silent, and the captain and Mrs. Gregory watch the events aboard the submarine on a reflector screen.
A Euclidean submarine and a flooded submarine lock on the Magic Island, with a yacht moored inside the lock.
Characters: Jerry, Joan, Captain Bradford, Mrs. Gregory, Pat, Tex, G-47, Johnson
Listen for: Whether the lock gate was broken or deliberately opened, and what G-47 intends for the captives and the submarine.
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.