It's been 13 years since Billy Bob Thornton created the indelible character of Willie Soke in Bad Santa. And as he finally reprises the role for Bad Santa 2 this year, Thornton is still bemused by the character's longevity, despite the fact that he knew it was a winner from the start.

Bad Santa 2Billy Bob Thornton stars in 'Bad Santa 2'

"We knew it had potential," he says of the original. "When I first read the script I was like, 'Wow, this would be the first time this has ever been done!' So we had some confidence that people would get it and would like it. But that it became that big? No. It's become iconic, and so we just wanted to get as close as we could to it on the second one. People ask me if it's as filthy as the first one, and I say, yes, maybe a shade more!"

He thinks that waiting this long helped make the sequel more interesting, because the characters are that much older. "Thurman [again played by Brett Kelly] is now 21 years old," Thornton says, "so you really do get, not only a sequel, but you see these people later on in their lives. And this movie is a lot more emotional than the first one. This one is a lot more a Christmas movie than the first one, because you see where Willie came from."

Watch the trailer for 'Bad Santa 2' here:


Where Willie comes from is his jailbird mother Sunny, played by Kathy Bates. "I think her character keeps the cynicism going," Thornton says. "Willie is still cynical, drunk and suicidal, but you can see in this one where he came from, and it makes sense. You can see that he's an abused and neglected child who grew up as a carny or as a grifter. And he's drunk all the time because probably the bane of his existence is that he does have a little hope. If he had no hope, who cares? But since he does, he sees himself and this kid, Thurman Merman, who never had a chance either. So that's what makes it like the darker version of something like traditional Christmas movies like It's a Wonderful Life or Miracle on 34th Street."

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And Thornton says Willie is loveable because he says what most people only think. "I mean how many times have you ever been in a supermarket, or anywhere, and you just can't believe the stupidity," he laughs. "And every now and then you do want to say stuff like that. So yeah, I guess most characters I've played are ones that can get a little cathartic."