Spoilers! How those great 'It: Chapter 2' cameos came to be – plus the one that got away

Spoiler alert! What follows contains light reveals from "It: Chapter Two."

With two casts, two movies and just as many timelines, the "It" horror franchise is getting to "Avengers"-levels in terms of scads of people running around.

Of course, it's all hands on deck when evil Pennywise (Bill Skarsgard) comes to town to prey on the children of Derry, Maine, every 27 years, and director Andy Muschietti's new "It: Chapter Two" sequel (in theaters now) stars an adult Losers' Club (including James McAvoy, Jessica Chastain and Bill Hader) that takes on the author Stephen King's infamous sewer-lurking clown for all the marbles.

But there are three new faces who make an appearance in "Chapter Two," and Muschietti explains those fun cameos – plus one that didn't work out that would have warmed the hearts of King fans.

Seriously. Now's your chance to bail if you don't want to be spoiled.

Peter Bogdanovich came into the picture.

Early on in “Chapter Two,” we’re reintroduced to one of the chief Losers, Bill Denbrough (McAvoy), who has left Derry behind to be a horror novelist and Hollywood screenwriter – though he’s known for not being able to write a good ending. Bill is on the set of his new movie when the director he’s working with comes down via crane to give Bill some notes, and it’s Oscar-nominated filmmaker Peter Bogdanovich.

“It was very playful, like Peter Bogdanovich comes from the sky and just drops from above, like some sort of god, and then he goes back to the cloud,” says Muschietti, who cites the elder director’s “Paper Moon” as one of his favorite movies and calls Bogdanovich a good friend. “He can sit down for three hours and talk about Orson Welles and (Alfred) Hitchcock.”

Bogdanovich “hates horror movies,” but he did perk up when Muschietti told him he was about to film his “It” sequel. “He said, ‘You don't happen to have a role for an old director like me, do you?’ And I said: ‘You know what? I do.’ ”

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Stephen King rules in a new role (and almost made it a family affair).

The 71-year-old literary master of horror has made cameos in his adaptations before, including the original “Pet Sematary” and “Creepshow,” and even directed himself in “Maximum Overdrive.” But he gets a whole scene to own in “Chapter Two,” playing the oddball owner of a Derry thrift store where adult Bill finds his childhood bicycle.

“I love Stephen King and our relationship started after he saw the first movie,” says Muschietti, adding that he offered him a cameo during “Chapter Two” pre-production. “He said, ‘Yeah, but you know, you have to consider that I’m a jinx. Every movie that I'm on bombs.’ And I said, ‘OK, well, we'll do it anyway.’ ”

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The scene was originally supposed to be just a small interaction between the owner and Bill, but King and Muschietti “started spitballing ideas" to make it more substantial, like having the author's character give Bill a hard time about his stutter.

The “It” director also reveals that there was a longer version of the scene in which Bill enters the thrift shop and there’s a flashback to 1989 with his teen self (played by Jaeden Martell) and fellow Loser Beverly Marsh (Sophia Lillis) having a romantic moment in the store. The younger version of the shopkeeper would have been played by King’s son Joe Hill, a horror novelist of note himself whose “NOS4A2” is now a TV series on AMC. Sadly, Hill's cameo was scrapped before being filmed, because the scene “didn’t have a real dramatic function.”

Andy Muschietti finally gets his own Hitchcockian moment.

Eagle-eyed audience members will notice that the Argentinian director put himself in a pharmacy scene perusing the aisles while the Losers’ resident hypochrondriac Eddie Kaspbrak (James Ransone) picks up a prescription – a callback to a similar sequence in the first “It” with Jack Dylan Grazer as Eddie.

Muschietti says he was supposed to be in that 1989-set scene, in the exact same spot, but the film's editor “couldn't make it work because I wasn't there long enough or I just walked out (at the wrong moment), so it ended up cut.”

So when it came to do the “Chapter Two” version, he made sure he stood there “for the whole scene,’ ” Muschietti says. “It's fun to be watching the movie and some people know my face, and you hear these murmurs.”

This article originally appeared on USA TODAY: 'It 2' spoilers: How the cool cameos happened in Stephen King's sequel