Escape's "Conquerer's Isle" begins with a burst of organ music and then draws us into the story of a lost Navy bomber crew in the South China Sea during WWII. Their plane is damaged, lost in a typhoon, and then forced to make an emergency landing on a small uncharted island.
Not long after they land the three Navy flyers are greeted by one of the island's residents, Dr. Grove, who takes them to a mysterious elevator. They don't want to accompany him, but he insists. Dr. Grove then leads them down into a wondrous underground city that belongs to a civilization of advanced human beings. Their community is one of advanced learning and evolved understanding. It is populated by humans who have been drawn to the island by telepathy. They are "the next stage" of evolution and their underground realm is where they study, build, and prepare for the day when their numbers are large enough to take over the Earth. At that point, they will become the "friendly guardians" of the rest of humanity. The Navy flyers trapped in this world are now their pets.
"Conquerer's Isle" was written by Nelson Bond and adapted for radio by John Dunkel. It was produced and directed by Norman McDonald. Dr. Grove was played by Bill Johnstone. Lieutenant Brady was played by David Ellis and Dr. Gorham was played by Ted von Eltz. Special music was arranged and played by Ivan Ditmars. This episode aired on March 5, 1949.
(Image from Wikimedia Commons)