> Filming on The Thing started on October 25, 1950, at RKO soundstages (one of which had been used for Citizen Kane, 1941) with an A-level budget set at $1.3 million (later to increase to $1.6 million). By the end of November the cast and crew went to a large icehouse in downtown Los Angeles to film shots where the actors' breath needed to be visible in the cold. Then it was off to Montana where they intended to film the expedition and saucer exteriors. Unfortunately the producers didn't realize that the snow in that part of Montana wasn't really adequate for their needs so they only got a few shots there. Additional shooting was done on a North Dakota set using stand-ins for the actors. The flying saucer sequence ended up being filmed at the RKO Ranch in Encino, California, using fake snow in front of an extensive curved backdrop.

> In regard to the music score, The Thing is one of the earliest science fiction films to use a theremin, an electronic instrument played without touching it. The theremin's eerie whine had earlier been used in thrillers like Spellbound (1945) and The Lost Weekend (1945), but henceforth it would be associated primarily with horror and science fiction thrillers.

> James Arness, later famous as Marshall Dillon on TV's Gunsmoke, was cast as The Thing and at the time he was just a struggling movie actor. In his few brief appearances as the creature, it's difficult to get a very good look at him; apparently a lot of close-ups were filmed but most were later removed because they were too obviously fake. As documented, Arness reported to the set two months prior to filming for the development of the make-up design, which took two hours each day to apply. At least their efforts weren't in vain: One day Arness and the make-up man took the Thing's claws to a drive-in restaurant where they startled the unsuspecting waitresses. Yet, despite the film's subsequent success, Arness was reportedly embarrassed by his role as The Thing for the rest of his life and didn't even attend the film's premiere.