One uphill battle of It: Welcome to Derry is that, at this point, the titular entity is a very familiar fear to audiences. Between King’s classic novel and the movie adaptations that inspired the new series, we’ve seen Pennywise do some terrifying things—so given a fresh crop of characters, mostly with largely unknown fates, Welcome to Derry needed to prove really quickly that it still had a lot of bite.

Best way to do that? Kill a bunch of your fresh-faced child actors.

The opening of Welcome to Derry‘s premiere—a gruesome scene we’ve been thinking about since it was screened at San Diego Comic-Con over the summer—sees a young boy named Matty (Miles Ekhardt) try and get a lift out of the cursed titular town, only for his would-be rescuers to be revealed as one of the entity’s manifestations, leaving the poor kid’s fate sealed as he bears witness to the birth of a blood-covered demonic baby that promptly lunges at him.

But Matty isn’t the only kid who ends up biting it over the course of the episode… most of the new kids set up as Welcome to Derry‘s next generation of protagonists end up being slaughtered in the episode’s climactic moments. Lilly (Clara Stack), Ronnie (Amanda Christine), Phil (Jack Molloy Legault), Teddy (Mikkal Karim-Fidler), and Susie (Matilda Legault) form a kind of neo-Loser’s Club over the course of the premiere, trying to figure out what happened to their classmate Matty, only for the demon baby to make a shock return during the climax of the episode, trapping the kids in a theater as all but Lily and Ronnie are gruesomely killed.

There was a version of the episode where all of the kids made it out of the movie theater incident in one piece. But speaking to Entertainment Weekly, the Muschietti siblings, Barbara and Andy, revealed that the gory twist was developed in secret with themselves and showrunners Brad Caleb Kane and Jason Fuchs after the original pilot script, with the kids surviving, had been sent to HBO executives. The twist was then revealed when the team went on to pitch the whole series, in a suitably dramatic fashion, which feels necessary when the pitch includes “hey, we want to kill so many kids on this show.”

“So the network didn’t know that was going to happen in the context of the pitch,” Fuchs told EW. “We had a wall with headshots of child actors who would’ve played the kids in [episode] 101. Andy [Muschietti] theatrically stood up as I was pitching. I got to the part where all of them, other than Lilly and Ronnie, being eaten. Andy pulled the paper down, and there was a whole other group of kids [headshots] under there. I’ll never forget seeing their faces and feeling like, ‘If we can replicate their reaction in the room with audiences at home, we’ll have a really interesting, exciting, satisfying way to end episode 1.’”

“This is strategically a devastating event to set the audience into that sense of ‘nothing is safe in this world,’” Andy Muschietti added, “We kind of trick the audience into thinking that these are the new Losers. Well, guess what? I guess they’re all dead.”

HBO was at least on board with letting it all happen (among other things, apparently), so now Lilly and Ronnie are going to have to find some new friends to confront the eventual murderous clown that’s stalking their town. They made it out of episode 1—will they make it out of the season?

It: Welcome to Derry is now streaming on HBO Max.

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