Open Question: Are there any movies you're too afraid to watch?

I won't lie and say that nothing scares me anymore. In fact, even though I didn't love the film, Other Mommy produced a couple of jump scares from me when I watched it last night. I like and often seek out horror movies and I’m fairly hardened to them at this point. That said, I'm not sure how many times I started Michael Haneke's 1997 film Funny Games before I finally watched it. I'd admired the Haneke films I'd seen up to that point, but I'd... heard things about it. And whenever I'd watch the opening the combination of a smiling family, aggressive music, and the bold, screen-filling title card made me opt for something else. I eventually did watch it—and like it—but it took a while. But there are other films I'm sure will upset me for one reason or another that, whatever their historic importance, I keep pushing down the "horror movies to watch" queue. (Sorry, Martyrs. Apologies, Cannibal Holocaust.) So, let's throw out a question fitting for the season: What movies make you fear the thought of watching them for the first time?