It: Welcome To Derry Is A Surprise Companion To Another Stephen King TV Series

We all float down here: This article contains spoilers for "It: Welcome to Derry" season 1, episode 1, "The Pilot."

The titular villain from Stephen King's "It" is an ancient and malevolent entity who's far more than the demonic clown Pennywise (Bill Skarsgård). It's also notorious for being one of the most widely-appearing antagonists in King's work, second only to Randall Flagg. A powerful alien creature from another universe, It is connected to a whole bunch of King's stories, and various works allude to its existence. 

Since the story of "It" already has plenty of substance to chew without bringing the whole Stephen King Universe into it, it's understandable that adaptations have tended to downplay this aspect. However, the "It: Welcome to Derry" season 1 premiere is extremely quick to lean on elements that feature in the "It" narrative but exist in other King stories as well – to the point that the show soon starts to seem like a stealth companion piece to its fellow King lore mix-and-match series, "Castle Rock."

Hulu's ambitious two-season horror show "Castle Rock" is notorious for taking place in the titular Maine small town — the setting of numerous King stories — and cramming as many elements from the author's various works into the plot as humanly possible. What's more, the show famously features a post-"It" Skarsgård playing yet another mysterious entity known as the Kid. With Skarsgård back in the Pennywise role and the story taking place in King's other famous small town, "It: Welcome to Derry" already had its share of thematic similarities with "Castle Rock" before the show's first episode started highlighting other King-verse elements.  

The clever thing about "The Pilot" is that the elements it introduces all technically belong in the "It" canon. However, much like the monster lurking in the heart of Derry, they also have connections to other King works, which means that the episode manages the rare feat of both keeping its narrative self-contained and expanding it far beyond the scope of the show's source material.

For instance, the episode's "duck and cover" mascot Bert the Turtle and Lilly's (Clara Stack) prominent turtle-themed bracelet are references to Maturin, a turtle deity that appears in the "It" novel as well as King's "The Dark Tower" books. The notable attention paid to the infamous Juniper Hill asylum is also noteworthy, as the important "It" location is also in a good dozen other King works and adaptations ... including "Castle Rock," as it happens.

There's also the matter of Dick Hallorann (Chris Chalk), a character who does have a minuscule presence in the "It" novel, but who's far better known from his role as Danny Torrance's mentor and fellow Shining user in "The Shining." Hallorann has a significant part to play in "Welcome to Derry," and while his inclusion makes sense since he's a part of the town's history, it's also a page right out of the "Castle Rock" playbook.

(Not that I'm complaining, mind you. "Castle Rock" rules, and based on the first episode, so does "It: Welcome to Derry.")

To be fair, "Welcome to Derry" is a very different beast from the mystery thriller-style "Castle Rock," thanks to its legitimately disturbing scenes and the patented, predatory "It" atmosphere. Not everyone buys the comparison between the two shows, either, even within the production team. In fact, Brad Caleb Kane, who created the show with Andy and Barbara Muschietti, has specifically crowned "Castle Rock" as the interconnected Stephen King Universe show. "The decision was made early on to tell a story that's specific to Derry in 1962 and not necessarily do a lot of cross-pollination in the King Universe," Kane told Entertainment Weekly. "There is a specific show for that. It's called 'Castle Rock', and you can go watch it." 

However, Andy Muschietti's comments in the same interview suggest the series' overarching storyline will embrace "Castle Rock"-style cross-pollination, albeit on a different, potentially grander level: 

"The idea, on the longer arc of the series, is to open the door to that bigger, wider mythology to see the iceberg under the water and everything that is not perceivable by humans. I can't tell you too much about seasons 2 and 3, but we are gonna see more of the mythology and the world that is behind the veil." 

There are many things to learn about "It: Welcome to Derry," which originally stemmed from Mike Hanlon's (Isaiah Mustafa) "It Chapter Two" research interludes that delved deep into Derry's dark history. "Welcome to Derry" may intend to take a far deeper dive into King's overarching mythology, and only time (and potential future seasons) will show how far the series is willing to go. 

"It: Welcome to Derry" season 1 is streaming on HBO Max.