Stephen King knows horror. He’s spent the last few decades at the top of the bestseller list, raking in mountains of cash by giving readers the creeps. While King’s tales of terror are loaded with the supernatural, the author understands that to make all those paranormal shenanigans truly terrifying, they need to happen to real, everyday people. The otherworldly needs to come creeping into our world, and make us realize there’s a night side lurking out there, full of things waiting to grab us.

Which is what makes King’s novel The Outsider, and its new HBO adaptation, so chilling. Adapted by The Wire writer Richard Price, HBO’s The Outsider is the ultimate tale of otherworldly nightmares creeping into our existence. It starts off seeming like a standard, if particularly gruesome, true crime story. And then the real nightmare begins.

The Outsider begins in truly ghoulish fashion with the discovery of a brutally murdered child in a small Georgia town. The case hits local detective Ralph Anderson (Ben Mendelsohn) extra hard, as he’s still grieving the sudden death of his own son. As Ralph and his fellow cops gather evidence and interview witnesses, a stark, disturbing, but unquestionable picture comes together. All that evidence, and all of those witnesses, place the blame for the killing on English teacher (and little league coach) Terry Maitland (Jason Bateman). Since it’s a small town, everybody knows everybody. Ralph and Terry are on a first-name basis. And by all accounts, Terry is a nice, ordinary guy – certainly not the type of monster who would mutilate a child.

But the evidence is overwhelming, and Terry is hauled in without questioning. But the case begins to unravel just as quickly as it came together. Yes, there’s plenty of evidence that links Terry to the murder – fingerprints, DNA, security camera footage – but there’s also plenty of evidence that puts him in the clear. There’s almost inconvertible proof that Terry was 70 miles away when the murder was taking place. Just what the hell is going on here?

What follows is a series of twists and turns that will leave audiences shocked, surprised, and scared. Price deftly takes King’s prose and works it into a living nightmare – yes, there are supernatural doings afoot here, but they never seem out-of-this world. The grounded atmosphere of the show makes everything extra real, and therefore extra creepy.

Mendelsohn anchors it all. The Australian actor has quickly risen to be one of the best in the biz, always turning in a memorable performance. But Mendelsohn’s somewhat gruff nature, and his keen ability to seem menacing, has lead him to a steady stream of bad guy roles. Which makes his part in The Outsider extra appealing. Here, he’s playing a genuinely good guy, and it’s refreshing to watch the actor be on the other side of the law for a change. His Ralph Anderson makes some big mistakes, but he’s also the type of guy who will do whatever it takes to make up for them. He’s a sturdy, steady presence, with Mendelsohn approaching the character with a light touch – letting his sorrowful eyes do most of the heavy lifting.

Mendelsohn is backed-up by a swell supporting cast, including Mare Winningham as Ralph’s wife Jeannie, and character actor extraordinaire Bill Camp as Terry’s lawyer. Then there’s Cynthia Erivo, the co-lead of the series. Erivo doesn’t enter the show right away, and she and Mendelsohn sadly don’t share too much screentime together, but her presence is key to the series’ success. Erivo plays Holly Gibney, a private eye who gets brought in to get to the bottom of things. As Ralph deals with matters back home, Holly hits the road, and soon discovers several other shocking child murders with similar scenarios: a suspect was arrested based on overwhelming evidence, and then new details emerged strongly contradicting that evidence.

If The Outsider were an X-Files episode, Ralph would be Scully – the level-headed, science-based non-believer who has a hard time swallowing the paranormal. Which would make Holly the show’s Mulder. Holly, who is unconventional – to say the least – has a much easier time accepting things that go bump in the night. “I have no tolerance for the unexplainable,” Ralph tells Holly, leading Holly to reply: “Well then…you’ll have no tolerance for me.” Holly is somewhere on the autism spectrum with a heavy dose of OCD, but Erivo handles all of this deftly. She doesn’t turn Holly into a caricature, or lean heavily on tics and over-the-top actions.

Subtlety is the name of the game here. If the actors – and the material – wasn’t subtle, The Outsider would capsize, bogged down by the weight of how impossible the subject matter is. There have been many Stephen King adaptations lately, on screens big and small. The Outsider is one of the best because it understands what makes the things that spring from King’s imagination so horrifying. When you pore over King’s prose, and when you watch The Outsider, you feel the gooseflesh prickle up on your arms, because through it all you can’t help think, “This couldn’t possibly happen…or could it?” How scary is that?

***

The Outsider premieres on HBO January 12.