From an opening scene featuring a suicide by decapitation to the show's main storyline about a man who's been trapped inside a cage in the abandoned wing of Shawshank Penitentiary for years without cause, the show oozes with the chilling, fearful ominousness that fans of King's work have become readily familiar with.
And then Melanie Lynskey shows up and reminds you that even the darkest days have rays of sunshine. Sure, painkiller-addicted sunshine with a sharp wit, dark background and possibly psychic abilities, but sunshine nonetheless.
Recently, ET spoke with Lynskey about her role on the hotly anticipated series, and the actress opened up about why this particular type of horror is something she finds interesting.
"I have no adrenal function. I don't get [startled]. Like, if something scary happens, I have no reaction," Lynskey shared. "My fiancé [the incomparable Jason Ritter] is constantly hiding behind back corners, crouching, trying to jump up and scare me, and I just go, 'Oh, OK.'"
"So those kind of slasher movies and jump scare things, I don't really get frightened by," she said. For her, the best kind of horror is the creeping dread and unnerving terror that is a staple of King's novels and the films adapted from them (at least, in the best examples).
"Creepy psychological horror is one of my favorite things," Lynskey shared.
Which is why Castle Rock is such a perfect fit for the New Zealand native. Not to mention the fact that she's been a life-long fan of the horror maestro's vast oeuvre, and is now a part of his fictional universe.
In the realm of Castle Rock, Lynskey plays real estate agent Molly Strand, a woman beset on all sides by people who don't trust her, including her sister (played by Allison Tolman) and people who are only looking to feed her addiction. (And also by a bunch of lonely, angry children wearing creepy animal masks, who have decided to set up a mock courtroom to sentence each other to death for various crimes in a sick interpretation of Lord of the Flies -- but we're getting ahead of ourselves.)
Molly is addicted to painkillers and opioids, which she uses to drown out the chorus of voices she hears constantly in her head. However, despite what many may think, she's not crazy. In fact, Molly has what is called, in King's universe, the shining -- a psychic connection with others that allows her to hear their thoughts.
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What might be a blessing to some has been nothing but a curse for Molly. She's suffered her whole life struggling with powers she doesn't understand and can't control, except through drugs -- and those are getting pricey in the dilapidated city.
With the deadpan delivery and dry wit that she's shown her mastery of time and again -- in dramedies like Hello I Must Be Going (2012), Happy Christmas (2014) and last year's brilliantly twisted I Don't Feel at Home in This World Anymore -- Lynskey's addition to Castle Rock's cadre of relentless misanthropes, malcontents and madmen elevates the series to heights many horror shows (and King adaptations) have never reached.
In fact, Castle Rock isn't the first time Lynskey has been a major part of a TV series based on King's work. In 2002, the actress played the soft-spoken Rachel Wheaton in the haunted house mini-series Rose Red.
Unlike many of the film and TV projects attached to King, Rose Red wasn't an adaption of the author's work, but was an original script, penned by King, that was originally envisioned as a spiritual adaption of The Haunting of Hill House.
Castle Rock, however, is a far cry from Rose Red when it comes to the complexity of its story, the scope of its themes, the darkness of its deepest psychological depths and the intense fandom surrounding it.
With Castle Rock -- produced by J.J. Abrams, who previously adapted King's 11.22.63 for Hulu -- the actress has entered a whole new world of public attention and fandom scrutiny that she's never really experienced with her previous work in brilliant independent dramedies and prestige TV series.
"It’s a weird thing to have this huge response from such a huge crowd of people," the actress admitted. However, after her appearance at this year's San Diego Comic-Con, she's learned a great method for dodging the spotlight.
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"The trick that I learned was to just stay two feet behind Bill [Skarsgard]," Lynskey said of her co-star, who plays The Kid in the Cage and previously starred as Pennywise the Clown in the most recent adaption of King's It. "People are so excited to see him that you just become completely invisible."
Aside from the cast, the story itself is packed with in-jokes and world building that links many of the author's varied stories together, calling back to the events of Cujo, Stand By Me, Shawshank Redemption, The Dead Zone and Pet Sematary to name just a few.
For Lynskey, who has been an outspoken fan of the author's work since childhood, getting to see all the subtle references that helped build the universe was especially exciting, but there were so many even she missed a few.
"There were a couple things that went over my head a little bit, but were still very spooky and fun to read," she shared. "And then when they were explained to me it was like, 'Oh, that’s great!'"
It's the dedication to craft and storytelling (over gimmicks and meta-referential fan service) exhibited by the show's creators -- Sam Shaw and Dustin Thomason -- that Lynskey said makes it accessible to all fans, "Even if you don't have such an in-depth knowledge of Stephen King."
As the complex story of Castle Rock's first season unfolds, with the horrors and surreal nightmares that seem to be building up with every successive episode, it's Lynskey's Molly Strand that has the toughest job -- bringing a dryly comedic respite from the nail-biting tension in a way only she could ever pull off.
While fans explore the nuances of the cursed dying town and try to parse out the surreal scenes of school children holding a mock trial in a run-down motel (which remains the show's most inexplicable and yet fascinating vignettes thus far), it will be Lynskey's beautifully troubled, painfully underappreciated and hilariously sardonic character that buoys viewers and brings them along for a shocking, chilling ride through one of TV's most loving crafted worlds.
New episodes of Castle Rock drop every Wednesday on Hulu.