What happens
Ken Thurston, the man called X, works with a Lisbon police agent after a spy is killed in his room in Lisbon, Portugal. Papers found there point to a source in Alamogordo, New Mexico, home of the secret White Sands rocket project. Thurston travels to Alamogordo and begins tracing the mailed reports through the local post office and the Desert Butte Hotel, where project engineers live. He meets a hotel hostess, Eva Lane, and librarian Miss Weatheridge, and starts to suspect people around him. Thurston's investigation is ongoing when this part of the episode ends. Starring Herbert Marshall as the man called X, the series aired on NBC on April 14, 1951.
Lisbon, Portugal, and Alamogordo, New Mexico, near the White Sands rocket project, 1951
Characters: Ken Thurston, Bartley, Eva Lane, Mr. Weston, Miss Weatheridge, Pagan Selchmiths, Bill Scorro
Listen for: Listen for the clues in the typed letters and the mail from Alamogordo, and for how Thurston's questions unsettle the hotel staff.
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.