The discovery of crop circles dates back to medieval times, it has been noted. They were-once called "mowing devils" as early in English literature into the 1500's. As of 1700 woodcuts shown having a "devil" with a scythe mowing the fields down. The Chinese are considered first to have found "crop circles" made of stone which match patterns discovered in recent time.
When Hynek and Quinn find the alien in the lab, Hynek takes a picture with his camera, he then says to Quinn stand closer as "I need something in the foreground to give it some scale" to which Quinn says, "foreground my ass" this is a nod to Hooper asking the same question of Brody in Jaws (1975).
East German born Thomas Kretschmann, who portrays former Third Reich Rocket Scientist & Nazi Wernher von Braun, stated he feels an aversion to taking Nazi roles in film. As of 2019, he has appeared fifteen times as a Nazi including a starring role as one of the leaders and architects of the Jewish Final Solution, Adolf Eichmann. He also portrayed Nazi Hermann Fegelein in the film Downfall (2004). Scores of videos were made with completely new subtitles inserted for various, mostly comedic, topics. Fegelein is the object of Adolf Hitler's anger and rants.
The episode is loosely based on the Chiles-Whitted UFO encounter of July 24, 1948.
At the beginning of the show there is town scene with a red and blue US mail box. US mail boxes were painted olive drab until 1955. The UFO encounter that this episode is based on (Chile's-Whitted) occurred in 1948.