World Gone Mad: 11 Scary Movies Where People Absolutely Go Wild

Shivers, also known as They Came From Within, is a horror film about how one day, the society of an upscale tower of apartments melts down in an orgy of sex and violence because parasites have infected them. It is directed by the master of body horror, David Cronenberg. The parasites seem to be a sexually transmitted menace as neighbors attack their families and other tenants. The Canadian Film Development Corporation eventually backed the film financially and called it "disgusting, awful, horrific, perverse."

The Spanish film Who Can Kill a Child? is about an island where the children have killed nearly all the adults and what happens to a couple who unwisely go there for vacation. Why the children have become homicidal isn't clear, but any children who go to the island become savage killers, and the adults have to do terrible things to defend themselves, hence the film's name.

Rob Jabbaz's film, The Sadness, is simply one of the most violent and craziest of these films. That should tell you something about how powerful The Sadness is. During a pandemic, people who have the virus, which has been mild, suddenly turn into raving and bloodthirsty maniacs who kill and violate others simply for the fun of it. It brings out all of the worst urges that you could ever imagine. You can feel this one in your bones.

What begins as a rehearsal at a remote schoolhouse for a troupe of dancers turns into chaos in Gaspar Noé's psychological horror film Climax. The dancers, who already dislike each other, don't know that one of their numbers has dosed the sangria with LSD. A spiral of rage and hatefulness follows, resulting in a large body count.

The Signal is an anthology film directed by David Bruckner, Dan Bush, and Jacob Gentry. In it, a signal embedded in television and radio broadcasts drives people insane. People affected by the signal start taking out their buried grudges in horrifying ways on the people in their lives.

Mom and Dad is a black horror and comedy film starring Nicolas Cage and Selma Blair. Radios and television sets start broadcasting static, making parents turn on their children. It's the opposite of Who Can Kill A Child, where the kids are now on the run. Of course, watching Nicolas Cage become a homicidal maniac is always entertaining.

John Carpenter's In the Mouth of Madness has a different explanation for the plague of madness. The books of a famous author, Sutter Cane, are the source of the brutality. People start to commit violent acts and mutate. It turns out that the power of the belief that the public has in Cane's work cause "The Old Ones" to come back to Earth to destroy the world.

At Belko Industries in Colombia, all employees have trackers implanted at the base of their skulls. It is supposedly for their safety until the real purpose is revealed one morning at work. The building is sealed, and the timid employees are told they are part of an experiment. If they don't kill specified numbers of their co-workers, even more people will die.

George Romero's lesser-known horror film about society breaking down is The Crazies. The culprit in this film is the virus Trixie that was released into a town's water supply. People turn on their family members, and the government quarantines the town and drags people to camps to control them. This is the second appearance of actress Lynn Lowry on this list, who is equally as memorable in this film as she was in Shivers.

In a more comedic version of kids becoming psychotic murderers of adults, Cooties stars Elijah Wood and Rainn Wilson. They are teachers at an elementary school that gets a bad batch of chicken nuggets infected with a mind-destroying virus. The virus only affects kids that haven't gone through puberty, and those kids start to attack every adult in sight.

Although The Happening was mocked for being unintentionally funny, it belongs on this list. M. Night Shyamalan's film shows people suddenly committing mass suicide. As an eco-horror film, trees emit the toxin to deal with the human menace on the planet. While it was considered funny that trees would try and take the human race out back then, it is a little less funny now.

The Crazies (2010) is a remake of the George Romero film from the 70s. It follows the same basic plot as the original and is glossier but also even more nasty in certain respects. The victims of the Trixie virus start to mutate, and some of the kills are even more gory and devious. Brock Eisner directs the film and stars Radha Mitchell and Timothy Olyphant.