IT: Chapter Two is one of this year's most terrifying films, which is due in no small part to Pennywise the clown and the practical effects surrounding the character. There's a lot that makes Pennywise terrifying, and in this video we're going to talk a bit about his true form and what you might not have realized about the horror movie icon.

The choice not to use CGI for the most part is a big part of the villain's scariness. Director Andy Muschietti isn't afraid to use CGI, but prefers to use practical effects whenever possible. Bill Skarsgard's ability to manipulate his different body parts is one of the biggest talents he brings to the film. He's able to create Pennywise' unsettling grin, and has been doing it since he was a child in order to bother his brother. He's also able to manipulate his eyes individually, which has further contributed to the villain's creepiness.

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However, we're not just talking about how Skarsgard was transformed into this video. Instead, we're also going to talk about the monster's true form, which -- be warned -- involves spiders, which many people are afraid of. Check out the video below for more of what you might not have realized about Pennywise.

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 Both IT films are based on Stephen King's 1986 novel of the same name. Although the first movie was critically acclaimed and became one of the highest-grossing R-rated films ever, the sequel has fared a little worse. However, IT: Chapter Two is still having a solid run at the box office, especially considering its high MPAA rating.

It: Chapter Two stars Bill Skarsgård, James McAvoy, Jessica Chastain, Jay Ryan, Bill Hader, Isaiah Mustafa, James Ransone, Andy Bean, Teach Grant, Jess Weixler, Will Beinbrink, Xavier Dolan, Jaeden Lieberher, Sophia Lillis, Jeremy Ray Taylor, Finn Wolfhard, Chosen Jacobs, Jack Dylan Grazer, Wyatt Oleff and Nicholas Hamilton.

KEEP READING: It: Chapter Two Ignores the Scariest Part of Stephen King’s Novel