Producer Dino De Laurentiis was very unhappy with the werewolf used in the film. He was disappointed in both the way it looked and the way the costumed actor moved. This proved to be a bit of an insult to the actor wearing the suit as he was an accomplished modern dancer and was hired specifically for his movement skills.
At a personal appearance in North Hollywood, California, in the fall of 1999, Gary Busey discussed his experiences in making this film- including doing all his own stunts. In the film's ending, where he is thrown around the room, Busey said this was achieved by having him (off camera) run and jump on to an air-compressed catapult which would then launch him through the air and into various pieces of breakaway furniture. He sustained an actual injury in the part where he lands into the mirror due to the artificial glass. This is evidenced in the film where a piece is seen embedded into his arm (which bleeds) as he falls to the ground. He went on to say that his reaction of the werewolf breaking through the wall was genuine as there was no rehearsal of that scene and it was completed in a single take.
The werewolf dream sequence utilized a total of seventy extras that were divided up into four groups with various levels of make-up and costume. These ranged from approximately ten principal actors used for close-ups and action shots, having the most refined looks, while the remainders were just made to appear menacing and fill up the rest of the church to give it a full house appearance.
Complete construction of the werewolf costume took three months. After finalization of the shape and design, using three-dimensional clay heads, the entire costume was made of foam and polyurethane and was covered with actual bear hair. The head of the costume was mechanically operated by six people from a distance of up to thirty feet away.
The Coslaw residence was an actual home used in Wilmington, North Carolina. Though the interiors were a set on a sound stage, the actual home itself was relocated in the 1990s to another area in town due to a massive shopping center that was built in it's place.
The fireworks on the bridge scenes were filmed on two separate occasions, months apart. After principal photography was completed, in the fall of 1984, they discovered a continuity problem. The wide shots and close-ups of Marty lighting the fireworks didn't match. They returned four months later to re-do these scenes, and by then (due to the seasonal change) much of the foliage and trees had lost their leaves. Great lengths were taken in the close pick-up shots not to show this in the background.
Tarker's Mill, when the action takes place, is a fictional town within the Stephen King universe. It borders locations of other King's works also adapted to film, such as Chester's Mill (Under the Dome), Derry (It) and Castle Rock (Needful Things, Cujo and Pet Semetary), among others.
Both Everett McGill and Gary Busey would eventually come to their demise at the hands of Casey Ryback played by Steven Segal in Under Siege and McGill in Under Siege 2: Dark Territory. Busey in a submarine that blows up in Under Siege and McGill on a train kitchen in Under Siege 2.