A friend of mine wanted to watch "Fall" on Netflix. I can deal with horror, blood, guts, gore, etc., but this may be the most terrifying movie I've ever watched. (Context: two women climb to the top of a 2000 foot / 600 m tower and get trapped there.) There were many points where I literally had to cover my eyes and look away. I became dizzy and disoriented, weak in the knees, my whole body was sweating, and I was drenched in cold sweat by the end of the movie. I think I had curled into a fetal position at one point.
I'm not afraid of heights per se (planes, skyscraper windows, lighthouses, high enclosed spaces are all fine), but I don't deal well with unenclosed high spaces. I've never had such a physical reaction like this before.
If you're sensitive to heights, I would recommend either AVOIDING this film, or watching it if you like to be terrified. I'm tempted to watch it again and see if I can use breathing exercises or similar to try to get over this phobia.