This Halloween, horror movies will definitely be in demand, with people trying to scare each other off. But how exactly does it feel like to be in one of these terrifying films, staring at death straight in the eye?

This is what the Washington D.C.-based American Chemical Society tried to explain in a fun and scientific video it uploaded in time for Halloween.

The video explained the feelings of a victim being chased by a serial killer in a slasher film using chemical reactions and events that are happening in the brain.

According to the video, reposted on the Independent website, the experience of a victim in a horror film is a little close to what is being experienced by a viewer, but only more intense.

Like the viewer, the people getting chased through a slasher film also first experiences fear.

The American Chemical Society described fear as "a cognitive response that alerts us in the face of trouble."

Fear, according to the video, triggers a chemical process that allows our body to seek safety. When a person experiences fear, sensory information is sent through a person's central nervous system to a region of the brain called thalamus.

The thalamus, which acts like a switchboard, signals other parts of the brain, including the hypothalamus, which controls the "fight or flight" response. This then triggers the adrenal gland to produce adrenaline, which gets a person amped up in the face of danger.

The video also explains how and why a person in danger resorts to screaming. According to the American Chemical Society, it is the body's way of sharing information about being in a state of horrified brain chemistry.

In the video, pain is also scientifically explained as a trigger for sensory neurons called nociceptors to send a message to the brain that whatever the painful experience is should be avoided.