Back in 1984, 85 or so, Laurel Productions created a half-hour horror series called "Tales From the Darkside". Here's how the intro went, narrated over creepy scenes of vacant forest, streams and fields: "Man lives in the sunlit world of what he believes to be reality. But, there is, unseen by most, an underworld, a place that is just as real, but not as brightly lit... A Darkside... Then the title flashed.
My favorite episode was the one about the little white demon that came out of the little door in the wall next to the bed. A girl rented out the room and by the end, the monster killed her. I forget if he dragged her inside the small doorway.
The movie wasn't half as good as some of the episodes. I hope they bring it to DVD someday. It was on VHS awhile back, but it's gone now.