Billy Bob Thornton admits he was blind drunk shooting 'Bad Santa' scene

There's a reason why Billy Bob Thornton was so convincingly drunk during that fateful scene in Bad Santa where he makes rather an exhibition of himself at the shopping mall grotto.

A model donkey gets kicked to death, and parents are soon fleeing the scene as Santa rolls around in a pit of his own regret, before wetting himself.

As it turns out, Thornton was pretty hammered at the time.

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Speaking to Entertainment Weekly, he admitted that he has 'a method actor aspect to myself'.

“I was drunk. It’s so obvious,” he goes on.

“I drank about three glasses of red wine for breakfast. That was just an appetiser. Then I switched over to vodka and cranberry juice and then I had a few Bud Lights.

“By the time I got to that scene there I barely knew I was in a movie. The fact of the matter is I was supposed to be standing on the escalator. It dumps me out and it literally woke me up and that’s what’s in the movie.

“And I get up, standing around because I thought I woke up in my house. And then I remembered what I was supposed to do. I was supposed to go there and fall down in all those gifts and be horrible in front of the kids.”

Bad Santa, produced by the Coen Brothers and directed by Terry Zwigoff, has become an alternative Christmas classic.

It found Thornton's Willie Soke as a deadbeat safecracker who, with his accomplice Marcus (Tony Cox), robs department stores during the holiday period.

While it made $76.5 million worldwide, a less successful sequel, starring Thornton and Cox alongside Christina Hendricks and Kathy Bates, bombed in 2016.