Ever since the invention of motion-picture cameras, filmmakers have been searching the darkest recesses of their brains in an effort to come up with the next great movie monster. From George Romero’s zombies to Wes Craven’s Freddy Krueger, the villains that have most memorably terrorized the silver screen have mostly been creatures quite unlike those found within our physical realities, providing a safe distance from the fear we feel while watching them stalk and slash. When we go to bed, we can be pretty sure that we won’t be torn apart in our sleep by a werewolf or feasted on by a thirsty vampire. Freddy isn’t likely to get us either.

But one thing we cannot promise ourselves is that we’ll be safe from the scariest monsters of them all: the human beings we’re forced to share this planet with.

It is for this reason that no sub-genre of horror is more genuinely terrifying than the home invasion film, which preys upon the very real fear of the safest place in your world being flip-turned into a living nightmare. Countless films released in the last several decades fall under the home invasion umbrella, from 1967’s Wait Until Dark to 2011’s You’re Next, but it wasn’t until Bryan Bertino made his own contribution to the sub-genre that the home invasion film truly reached its pinnacle of terror. Released in 2008, The Strangers upped the fear factor by throwing motive completely out the window.

There’s absolutely nothing deceptive about the simplicity of Bertino’s premise. In The Strangers, James Hoyt (Scott Speedman) and Kristen McKay (Liv Tyler), whose troubled relationship is given a wonderfully nuanced introduction within the first 15-minutes, are spending the night in a remote vacation home. Around four in the morning, they receive a knock on the front door from a young woman who claims to be looking for a friend of hers; and soon thereafter, a trio of masked maniacs break into the home and terrorize the couple. Why, you ask? That’s a question directly addressed in Bertino’s script, and the answer sends chills up the spine just thinking about it.

“Because you were home,” answers one of the masked intruders.

More than merely a creepy tagline, that bone-chilling reveal hammers home the entire theme of The Strangers, which is that sadistic killers don’t need a reason to make you their next target. It’s comforting to believe that you need to wrong someone in order to become their enemy, but the reality, as is terrifyingly on display in The Strangers, is that your peaceful existence can be shattered simply because you were in the wrong place at the wrong time. And sometimes, as the world learned courtesy of the infamous Manson Family murders of 1969, which loosely inspired Bertino to pen this very film, that wrong place can be within the walls of your own home.

Like the real-life murders of Sharon Tate and friends, there’s really no point to the brutality on display in The Strangers, and though many over the years have criticized the film for that, it is my belief that it’s actually the single most chilling aspect of it. Right out of the gate, a narrated sequence (a nod to The Texas Chain Saw Massacre) more or less lays out everything we’re about to see, letting us know that the two characters we’re about to meet will not survive the night. Less than 80-minutes later, as promised, James and Kristen are uneventfully stabbed to death; and just like that, the film ends. No twist. No surprises. When it’s over, we realize there was no point to what we just witnessed. And if the palpable terror of that pointlessness doesn’t linger with you long afterwards, well, it sure does for me.

Everything about The Strangers is quiet and understated, which is a huge reason why it’s so effective at imparting the fear that it does. In the most chilling moment, Kristen is pouring herself a glass of water in the kitchen while the so-called “Man in the Mask” watches from afar – something we see but Kristen does not. The brief glimpse of the masked madman in the background, which is purposely out of focus, is the visual equivalent of the iconic reveal from When a Stranger Calls that the killer is calling from inside the house, and it’s the complete antithesis of the jump scare that plagues so many horror movies. By showing us that the killer is inside the house, and then making us wait for him to strike, Bertino imbues the bulk of the film with a tension so thick you can cut it with a butcher’s knife, proving with only his first film that he understands precisely what makes a horror film scary. Truly *scary*.

The Strangers doesn’t make you afraid to venture out into the woods with your friends, nor does it make you fear that your dead loved ones are going to come back from the grave and feast on your flesh. Rather, it makes you afraid of something you simply cannot escape doing each and every night: being in your own home when the sun goes down. Because you never know who might come knocking. And just being home might be enough to get you killed.

Can anything really be scarier than that?

Note: A version of this article was originally published on May 5, 2016.