"He's not even human, he's just pure evil," Skarsgard says of Pennywise
Credit: Warner Bros.

They both played infamously evil clowns, but It’s Bill Skarsgard sees some major differences between his Pennywise and Heath Ledger’s Joker from The Dark Knight.

“I think the biggest difference between Pennywise and the Joker character — or at least Heath Ledger’s interpretation — is that he’s far more based in reality,” Skarsgard, 27, tells PEOPLE.

“[The Joker] is sort of this social anarchist, crazy person, and I don’t think Pennywise is the same in that way. He’s not even human, he’s just pure evil,” he adds.

The boyishly handsome Skarsgard, son of acclaimed actor Stellan, and younger brother to fellow actors Gustav and Alexander, is unrecognizable as Stephen King’s Pennywise the Dancing Clown from his 1987 novel It.

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Bill Skarsgard
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In the book, which gained further popularity after it was adapted into a 1990 TV series starring Tim Curry, Pennywise is an otherworldly force of evil that feeds on children in the fictional town of Derry, Maine.

But Ledger’s Joker in The Dark Knight had bigger plans than just eating and scaring the bejeezus out of little kids. His version of the Batman villain, which earned him a posthumous Oscar, was hellbent on creating chaos, upsetting the social order and of course, killing “the Batman.”

For Skarsgard, Pennywise’s motivations are “less crazy” than the Joker’s plan to turn an entire city against itself. Not that his clown is a jolly Bozo either: “Of course, Pennywise is still dark and sinister — and he’s going after kids.”

While the characters have their differences, both Ledger and Skarsgard worked tirelessly to transform themselves. “Where I went with it was like, ‘What’s the most horrible thing that could happen here?’ And then I’d do that,” Skarsgard explains. “You need to access parts of yourself where you’re thinking about what’s the most disturbing or horrifying [thing to do], and then you have to commit to that.”

Skarsgard admits he had nightmares for weeks after It wrapped, saying, “It was very strange, it was almost like a really slow exorcism to completely let go of him.”

After Ledger’s death in 2008 from an accidental prescription drug overdose, rumors abounded that he “was taken down this dark spiral path to the depths of depression from his role as the Joker,” as I Am Heath Ledger producer and co-director Derik Murray told USA Today.

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Heath Ledger
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But his family and friends have vehemently dismissed the rumor. “Honestly, that’s been the biggest thing for us as a family,” Kate Ledger, Heath’s older sister, told the outlet. “He had an amazing sense of humor and certainly playing the Joker, for him it was one big gag. He had so much fun doing that. It was actually the exact opposite. There was no doom and gloom. … That was a shock to me that people even thought that, really.”

Despite Skarsgard’s bad dreams, he says, “I did have so much fun with the character, and I’m really looking forward to getting back under that clown makeup for the sequel.”