The Backrooms are a liminal space CreepyPasta setting where you’ve “no clipped” out of reality into and endless office maze of office corridors decorated in ugly yellow wallpaper and brown carpets illuminated by buzzing florescent lights.
Several video creators have run with this idea and produced some pretty convincing depictions of it. In the ones below, YouTuber Kane Parsons, AKA Kane Pixals, has filled in background lore where the Async Corporation has created (or possibly tapped into) The Backrooms as a potential money-making project, documenting their work as bland, 1980s-corporate speak promotional videos and handheld camera footage that have come down to us as grainy VHS copies. It’s a pretty-inspired mating of presentation format and subject.
And the people exploring the Backrooms start to realize that the deeper you get, the weirder things seem to be, and that there’s something else wandering those yellow hallways…
Evidently he’s doing all this in Blender, which you can download for free.
And there are lots more YouTube creators doing their own versions of the Backrooms…