1982 movie Halloween III: Season of the Witch is a movie about a company that created a new Halloween mask for children. This mask was heavily promoted by its creator and the media so it became "must have" for all of the kids in America.
The kids were all told they must wear their mask during a commercial on Halloween Night for a special surprise.
As you guessed, this company was run by satanists, and anyone watching the commercial while wearing the mask would end up dead.
Three more days til Halloween...silver shamrocks. That movie, while nothing to do with its 2 predecessors, was equally as creepy. Great comparison.