Have you watched "The Nightmare" on Netflix yet? As in, all of it? If the answer is "yes," you are a hardier mortal than I. Maybe it's because I live alone. Maybe it's because I've only tried watching it at night, with the lights out. Maybe it's because I've experienced the utter horror of sleep paralysis on more than one occasion and fear that watching the movie all the way through will somehow trigger it again. But whatever the reason, I haven't been able to finish "The Nightmare" yet. I have tried four times. I'm writing as someone who yawned through all three "Insidious" movies. I'm writing as someone who watched the excruciating "Martyrs" in a single sitting, no breaks. I'm writing as someone who has seen a lot -- a lot -- of horror films, and felt gripped by the hand of fear only a handful of times. But "The Nightmare" is different.