"The Scariest Movie Ever Made" is a Halloween series in which Film.com writers discuss and confront the most terrifying movie they've ever seen.

Describing what makes a film scary is a bit like explaining a joke — if you have to do it at all it isn’t likely to be very convincing. Fear is too personal, and thus too contingent: everybody responds to different things for different reasons. If you are afraid of clowns, you will doubtless be afraid of “It”. If dolls set you off, you’ll want to steer clear of “Child’s Play”. I know somebody so terrified of zombies that even “Shaun of the Dead” is a tough sit. There isn’t much of an argument to be had on this point. You can’t really convince somebody to find something scary, at least no more than you could convince somebody who doesn’t like mayonnaise to enjoy an egg salad sandwich. Which is to say that for all its enthusiasm in unpacking the psychological dimension of horror, criticism strikes me as rather ill-equipped to contend with fear. So in lieu of proposing an all-time scariest movie, let me change the parameters of the question slightly.

In 1971, experimental filmmaker Stan Brakhage made “The Act of Seeing With One’s Own Eyes”, a 40 minute silent documentary shot in a Pittsburgh morgue. The film is composed of nothing more than autopsy footage, captured candidly and graphically, and it has become almost a cliche to observe that, once you have seen it, its images cannot be forgotten. The bodies of men, women, and children are laid out on tables, undressed, wiped down, embalmed, and variously sliced open, cut apart, and skinned. Brittle chunks of ribcage are hacked away at, thick heads of hair are carved thinly off, and, in a moment that seems almost literally unbelievable, the skin of a man’s face is tugged down and peeled right off, the mortician’s gloved hands tearing flesh away like a bandaid. We tend to talk a lot about a sense of physicality in horror films, about a tactile presence of the body in the image. “The Act of Seeing With One’s Own Eyes” is a film of pure physicality: it is the physical divorced from the cerebral and the spiritual. It is corporeal cinema. Anatomical cinema. If “body horror” were not already a genre it would need to be invented to account for this.

Now, even real mutilation and gore may not trigger fear in certain viewers — I would think that in the very least those who practice autopsies themselves would be immune by now to their visceral impact. But this isn’t simply a matter of context or degree. “The Act of Seeing” is terrifying because of the way it forces us to confront the basic (and therefore fragile) physical qualities of the human body, which is reduced, over the course of the film, from human to material, or from a once-living person to something elemental and abstract. It’s scary because it makes us think about the one contradiction we’re fundamentally unable to reconcile: that consciousness, the great messy expanse of human experience, can somehow be contained in this unglamorous arrangement of flesh and bone and blood. In the human face we see life: thoughts, feelings, everything we know and are. But beneath the face, when it’s been peeled back uncaringly, and the body looks like spare parts? You don’t see thought and feeling there. You see nothing. You see meat.

To say that “The Act of Seeing With One’s Own Eyes” is the scariest movie ever made in some sense trivializes the depth and intensity of what it tells us — certainly this is a different experience than being spooked or startled by a blurry ghost or knife-wielding maniac. But then maybe that’s what makes it transcend the question of preference and taste. The effect of this film doesn’t rely on a fear of the images it offers. Neither does it seek out those afraid of death. All Brakhage asks of his audience is that they bring a body: this clumsy, delicate thing, blood coursing through it, brain matter for now still contained and in tact. (Nothing a saw couldn’t get through.) The film doesn’t really aim to scare you. It intends only to show you something so real and so inevitable that the only natural response is fear. In other words it gets under your skin.

Note: You can watch "The Act of Seeing With One's Own Eyes" in its entirety on Vimeo. DO SO AT YOUR OWN PERIL.