Castle Rock, the new horror anthology series from Hulu, surprised us by becoming one of our top breakout shows this summer. Inspired by the works of Stephen King, the series has already been renewed for a second season. As we head into the last two episodes this season, Ars caught up with co-creator Sam Shaw to talk about the nature of horror, common themes, and what we can expect from the series going forward.

(Mild spoilers below for the first eight episodes.)

Shaw and co-creator Dusty Thomason previously worked together on Manh(a)ttan, a series set in the New Mexico military encampment of Los Alamos, detailing the birth of the atomic bomb in the 1940s. Despite critical raves, the show never quite found its audience and was sadly cancelled after just two seasons.

Castle Rock shares Manh(a)ttan's small-town aesthetic, drawing in this case on iconic towns in horror fiction, notably the works of King and H.P. Lovecraft. "I loved the idea that there are these cursed places that have been the site of more than one nightmarish disaster that they rain down on their characters for decades or centuries," Shaw says. "Yet the town somehow persists."

The fictional town of Castle Rock features in so many of King's novels, Shaw and Thomason thought they could use it as an organizing principle for their storytelling. The series is less a direct adaptation of King's works and more new stories set in the fictional town that occasionally bump up against various books.

“The horror is as much interior as it is exterior.”

From The Shining and The Dark Half to more recent novels like Lisey's Story, King's approach to horror has always been as much about plumbing the darkness that lurks in the human soul as it is about monsters and violent carnage. "The horror is as much interior as it is exterior," Shaw says. "There's always a sense that there are quotidian, real-world horrors that coexist with the supernatural machinery of his storytelling, and sometimes the lines between them get blurred. By the end of the story, the monster has been vanquished, but those everyday horrors persist."

Castle Rock brings that same sensibility to its tale of a small Maine town rocked by a series of tragedies. It starts with the suicide of the local prison warden, Dale Lacy (Terry O'Quinn, Lost) and the discovery that he secretly kept a young man—known only as the Kid (Bill Skarsgård, It)—captive for decades. Not only has the Kid not aged, violent outbreaks seem to follow in his wake.

The biggest influences for season one are The Shawshank Redemption and The Green Mile—in other words, a prison-centric setting with themes of crime and punishment. Shawshank tells the story of a prisoner's disappearance, while Castle Rock's focus is the mysterious appearance of a prisoner nobody knew about, except the late warden. And the Kid, according to Shaw, is "a bit of a photo-negative of John Coffey's Christlike figure in The Green Mile."

But is the Kid truly evil? Is he a monster, a victim, or both? It's deliberately unclear; Skarsgård's performance of the Kid vacillates between vulnerability and ominous menace. Eight episodes in and he's still a cipher, in part because Shaw wanted to leave plenty of room for audience interpretation of the character.

"He's almost this screen that people project their ideas about the world onto," Shaw says. That said, "Bad fortune seems to follow him wherever he goes. Put it this way: if you were putting together actuarial tables for an insurance company, you wouldn't want to insure him."

Houston attorney Henry Deaver's homecoming is an homage to yet another common King trope: confronting one's past childhood traumas. "We would have been guilty of criminal malpractice if we had not built a season around the idea of adults who are reckoning with the traumas of childhood that have defined the trajectory of their lives," Shaw says. Henry went missing for several days as a child, right about the time his father died under strange circumstances, and he has lived under a cloud of suspicion ever since. Henry himself only recalls fragments of what happened. But from what we've seen so far, his past is inextricably linked to the current terrible events in Castle Rock.

The person who may hold the keys to that past is Henry's adoptive mother, Ruth (Sissy Spacek, Carrie, Bloodline), who suffers from dementia. We start to get a better sense of what some of those secrets might be in the season's heart-breaking seventh episode, "The Queen"—the most beautifully constructed, superbly acted hour of television you'll likely see this year.

Earlier, Ruth confessed to her grandson, Wendell (Chosen Jacobs, It), that she has become unmoored in time. She uses chess pieces scattered about the house to anchor her in reality. The entire episode is told from her point of view as she shuttles between the past and present, walking out of a conversation in the present and into a different conversation in 1991. All the while, she's playing a kind of cat-and-mouse game with the Kid. The episode culminates in a tragic twist that marks a turning point in the season, revving up into high gear what had until then been a slow burn.

The episode has deep personal resonance for Shaw, whose own mother suffered from dementia. She died unexpectedly a few days after he started writing the series. "It was like getting hit by a meteor," he said. "She was one of the great people in my life. I have come to have enormous admiration for the bravery that it takes to live your life in the face of those kinds of headwinds."

That loss naturally informed the storyline, notably in Ruth's refusal to leave her home ("I'd prefer to fall in my traces like the shield maidens") and in the chess pieces she uses to remind her of the present. As Shaw and his sister were going through their mother's belongings, it brought back all the memories of her life. "I started to think a lot about the way that objects become repositories for our memories, like talismans," he says. Familiar places can have a similar effect.

"That house is the place where [Ruth] knows who she is, where her story is alive," Shaw says. Take that away and she would become truly lost in time. Chess and other games and brainteasers in general are typically prescribed to help stave off dementia. And it's fitting that the chess set here is a gift from retired sheriff Alan Pangborn (Scott Glenn, Daredevil, The Leftovers), the love of Ruth's life, who has anchored her for so many years.

Castle Rock's penultimate episode drops tomorrow, with the finale slated for release on Wednesday, September 12. Expect the body count to rise even further as all those secrets simmering beneath the surface finally come to an explosive head.