Just looking at a razor blade makes me recoil. So if you really want to jangle my nerves (but why would you ever want to do that?), all you have to do is flash a razor blade onscreen in a movie. If you totally want to fuck my shit up, then have a character use a razor blade as a murder weapon in an uncomfortably long scene of raw killing. Apparently, the Oscar-nominated French film, A Prophet (Un prophète), has no goddamn respect for me and totally wanted to fuck my shit up.
Aside from that, Jacques Audiard's A Prophet (co-written by Thomas Bidegain) is a richly detailed and assuredly epic story of a teenage delinquent—a Frenchman of Arab descent—who uses his six-year prison sentence to educate himself. Sure, he learns how to read, but his real education is in the ways of the gangster. Specifically, he starts working with a group of convicted Corsicans who not only rule guards and inmates inside the jail but also dictate mob shenanigans on the outside.
At two-and-a-half hours (which honestly didn't feel that long even to someone as easily bored as I am), A Prophet, which takes place mostly inside the prison (with occasional dynamic scenes on the outside), is as immersive an experience as, say, Avatar. Seriously.
On a side note, lead actor Tahar Rahim may be scruffy, shaggy, and all kinds of dirty in the movie, but in real life he's a big helping of pure hotness! Seriously.