We watched Late Night with the Devil last night and I thought it was fantastic. I love stories about hubris, stories about the dangers of obsession with fame and power, and this is a brilliant example.
Basic premise is that a late night talk show host in 70's USA decides to bring an exorcist and her subject (a kid who can supposedly speak to the devil) onto the show to save faltering ratings. Even when it slowly becomes clear that - despite their assumptions - she is not a scam artist, he insists on persisting with the show, with disastrous results.
It is created almost entirely in the visual style of a real VHS recording of a 70s show, and it's one of the best horrors I've ever seen.