Many films have explored this feeling in a way that’s both compelling and unsettling.

Don’t get real get surreal.

Slow but suspenseful, it’s a horror thriller like few others.

Collage with images from ‘Eyes Wide Shut’, ‘The Thing’, and ‘Memento’

For a dose of biting social commentary.

Spoiler alert: Most of these are Hitchcock.

The performances are fantastic, of course, but that’s not it.

Sean Gullette in Darren Aronofsky’s Pi

Image via Summit Entertainment

It’s a terrific movie, but certainly not an easy one to get through.

KEEP READING:The Greatest Movies of the 1970s, Ranked

Stills from Persona, Eraserhead, and Daisies

Trevor Reznik looking at his frail body in the mirror in The Machinist

Image via Paramount Classics

Take Shelter Michael Shannon Storm Rain

Image via Sony Pictures Classics

Mrs. Iselin talking to a distressed Raymond, who’s covering his ears, in The Manchurian Candidate - 1962

Image via United Artists

The-20-Best-Political-Thrillers-of-the-21st-Century-(So-Far)

Tom Cruise as Dr. Bill Harford looking confused in ‘Eyes Wide Shut’

Image via Warner Bros. Pictures

Catherine Deneuve as Carol in Repulsion, looking in a mirror with her hands on her face.

Image via Compton Films

Dr. Christian Szell examining one of Babe Levy’s teeth with a metal tool

Image via Paramount Pictures

Kim Novak and James Stewart as Madeline and John pressed close together in Vertigo

Guy Pearce in Memento

Image via Newmarket Films

Kurt Russell R.J. MacReady in The Thing.

Image via Universal Pictures

Actor Gene Hackman as Henry Caul watching over surveillance equipment in Francis Ford Coppola’s movie, The Conversation

Image via Rialto Pictures