What happens
Captain Bradford and Jerry Hall join the Euclidian engineers Kiaps and Thales for a test flight of a rocket plane that is also a submarine, launched from the underwater city of Euclidia, 400 feet below the ocean surface. The captain hopes the flight will lay the groundwork for an escape, after which his formula could be used to gain control of the Magic Island and end the Euclidians' plans of world terrorism. Their orders keep them within 100 miles of Euclidia and below 50,000 feet, and Bradford questions the claims about the craft's safety and performance. The men rise through the lock, check the surface with a detection beam, and take off under power, reaching high speed while the craft's mechanics are explained. The episode ends with a radio disturbance suggesting another craft is on their course.
The underwater city of Euclidia, 400 feet below the ocean surface, and the rocket plane's flight above the ocean.
Characters: Captain Bradford, Jerry Hall, Kiaps, Thales, G-47
Listen for: Kiaps explaining how the rocket plane's gas fuel drives it at near the speed of sound, and the radio disturbance at the end that suggests another craft is on their course.
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.