As Stephen King fans eagerly anticipate the arrival of It: Welcome to Derry, a new HBO series developed by the creators of the recent It movies, including director Andy Muschietti, here’s a reminder that it’s not the first series to expand King’s horror world with original stories. While Derry riffs on flashbacks from the 1986 book to build a history for Pennywise’s reign of terror, the Hulu series Castle Rock also zeroed in on a picturesque yet cursed part of Maine explored in King’s many works. While the two shows will no doubt have many differences between them—Castle Rock was an almost entirely original creation; Derry draws from a specific novel as well as two movies—we’re anticipating similar tales of small-town terror and dread, with background characters brought to the forefront, tiny plot details getting intriguing expansions, and Easter eggs a-plenty. With that in mind, here are five things Castle Rock did so well we wish it had gotten more than two seasons. A Central Mystery Castle Rock’s two seasons followed almost completely standalone stories. But there were still similarities beyond sharing a setting. Both incorporated different moments in Castle Rock history, with criss-crossing timelines, shifting memories, and explorations of important events from different points of view. Both shared a fascination with perception in other ways too: what’s real, what’s being filtered through an unwell mind, and what’s being caused by supernatural interference? They were also both propelled by a central mystery—as you’d expect in a show with J.J. Abrams in its credits. In season one, attorney Henry Deaver returns to a hometown that was glad to see him leave. Once there, he must reluctantly face up to a troubled past—as a boy, he mysteriously vanished for a brief period that coincided with his adoptive father’s equally mysterious death—while being drawn into the case of “the Kid,” an unnamed and unaccounted-for prisoner being kept in an unused wing of Shawshank State Prison. Season two offers a backstory for Annie Wilkes, the unforgettable antagonist of Misery, as she becomes enmeshed in a terrifying cult that’s been waiting to reawaken beneath Castle Rock for centuries. Though Annie and Henry don’t meet, “the Kid” pops back up in a different guise, this time as “the Angel,” a spin on the character that underlines the dark revelations about him in season one. A Mix of Old and New Characters Annie Wilkes is the most famous Stephen King character to be featured in Castle Rock, but other denizens popped up: Sheriff Alan Pangborn, who appears in The Dark Half, Needful Things, and other works, is a key player in season one; various members of the Merrill family—a last name familiar across many of King’s stories—help steer events in season two. There are also some fresh creations who feel like they’re winking at the viewer, including Jackie Torrance—the niece of you-know-which Overlook Hotel caretaker in The Shining. But both seasons also bring in mostly new characters, including Henry Deaver and his family, especially his mother Ruth; Molly, Henry’s psychically gifted childhood friend and neighbor; Joy, Annie’s teenaged daughter; and the Howlwadaag siblings, Nadia and Abdi, who left Somalia for a better life in Castle Rock… but probably should have settled in literally any other town. Outstanding Casting Stephen King stories tend to attract top talent as well as returning talent; while season one’s main cast (André Holland, Terry O’Quinn, Melanie Lynskey, Jane Levy, Scott Glenn) was excellent, Castle Rock season one’s biggest coup was bringing Sissy Spacek—Carrie forever—aboard to play Henry’s mother, who suffers from dementia. The season two equivalent is Shawshank Redemption escapee Tim Robbins, who plays Pop Merrill, the slippery but layered patriarch of the Merrill family; he seeks to make certain amends as he faces his end from a terminal illness. He’s joined by Lizzy Caplan, who gives a searing performance as Annie, as well as Elsie Fisher, Robin Weigert, Barkhad Abdi, and others. In both seasons, of course, you get Bill Skarsgård. It hit theaters in 2017, Castle Rock season one was 2018, It Chapter 2 came out in 2019, and Castle Rock season two was also 2019. Though his Castle Rock character isn’t Pennywise, that same sinister energy seeps across all these projects. And we’ll soon get to see him back on the small screen, presumably leering from the sewers once again, in It: Welcome to Derry. Expanding Small Pieces of Lore to Build a History It: Welcome to Derry will no doubt emphasize how the town of Derry is a place where Bad Things Happen, so much so that when you move away—as the kids in It’s first segment do—you all but forget what happened to you there. Castle Rock also established that its town is deeply troubled; there’s no clown-shaped entity pulling the strings, but it has its own uneasy, seemingly cursed history. While Castle Rock is one of King’s most-used settings, the TV show stuck closely to the events that were directly related to its plots. But there were clues and references with a specificity beyond just bad vibes. In the first season, for instance, we saw newspaper clippings referencing a “rabid dog” (Cujo) and a shopkeeper going missing after an oddity store fire (Needful Things). We also see a tragic flashback that’s dated to “the fall after they found that boy’s body out by the train tracks” (as in the King tale The Body, adapted into Stand By Me). The implication is that there’s something in Castle Rock that turns people bad, and it even infects the physical landmarks that the show incorporates. There’s Shawshank, of course, but the show also draws on the notorious Juniper Hill psychiatric hospital, the Marsten House from Salem’s Lot (located in the neighboring town of Jerusalem’s Lot), and—perhaps most notably—the eerie quality that permeates the area’s woodsy wilderness. Twin Peaks wasn’t a Stephen King creation, of course, but that Lynchian idea that a forest can facilitate sliding boundaries between realities fits in perfectly here. Genuine Frights Castle Rock was scary. There was the creeping dread of the Kid’s strange powers, the unease Henry felt while poking into his own memories, the terror Ruth felt as she tried to keep ahold of reality—and a similar terror felt by Annie, whose mental illness slipped in and out of her control while very real (and yet very unbelievable) events happened around her. Also, yes, it had jump scares—not just from Skarsgård, though he is a reliable source of them and will surely be bringing more when he returns to Stephen King’s world very soon. Castle Rock seasons 1-2 are streaming on Hulu. It: Welcome to Derry’s first episode arrives October 26 on HBO.