The most shocking thing about It, something most fans only learned after being terrified in theaters by Stephen King's iconically evil clown, is that the actor behind Pennywise's red wig and clown makeup is, well, hot. In this behind-the-scenes featurette, exclusively debuting on ET, Bill Skarsgård reveals exactly what was required to become a creature "who can look very cute and sweet and childlike, but is hiding something terrifying."

"I do this thing with my lip. It's a thing that I've been doing since I was a little kid, and I always wanted to bring this, like, lip thing into a character," Skarsgård explains, along with how his "lazy eye" factored into his Pennywise transformation. "I just put all these things together to make as much of a weird, disturbing performance as possible."

Warner Bros. Home Entertainment

If it was weird and disturbing he was going for, Skarsgård, as directed by Andy Muschietti, pulled it off and then some. In my review of It, I wrote, "Skarsgård doesn't so much skew toward Tim Curry, the actor who first embodied the dancing clown, as he does an actual music box clown come to life, with a bucktoothed innocence barely veiling his far more perverse, even perverted, actuality. When Pennywise laughs, a chuckle that becomes a manic, maniacal giggle, it's equal parts silly and sinister, as are most of the choices Skarsgård makes in the role."

Here is the official breakdown of the bonus features for the movie's home release:

Pennywise Lives! - Discover how Bill Skarsgård prepared to portray the primordial creature known as Pennywise the Dancing Clown.

- Discover how Bill Skarsgård prepared to portray the primordial creature known as Pennywise the Dancing Clown. The Losers’ Club - Get up close and personal with the teenage stars of “It” as they bond together during the production.

- Get up close and personal with the teenage stars of “It” as they bond together during the production. Author of Fear - Stephen King reveals the roots of his best-selling novel, the nature of childhood fear and how he created his most famous monster.

- Stephen King reveals the roots of his best-selling novel, the nature of childhood fear and how he created his most famous monster. Pennywise Deleted Scenes – Eleven deleted or extended scenes from the film.

It is available digitally on Dec. 19 and will arrive on Blu-ray, DVD and 4K Ultra on Jan. 9.

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