I happened across Poltergeist 3 while channel surfing the other night. It was not a great movie, but it was fun-dumb instead of boring-dumb, so I ended up watching most of it. While the writing is so-so and the acting made me roll my eyes a few times, the movie is interesting for a technical reason. Almost all of the special effects were filmed in-camera. There were no blue-screen shots, no animated models, no CGI, nor very much of anything added in post production. Despite the movie's other shortcomings, I was impressed that the filmmakers created a nice spooky atmosphere with lots of supernatural goings-on using only costumes, props, mirrors, lighting, and dry-ice fog.
