David Harbour grew 'big old love handles' to play an ass-kicking Santa Claus in Violent Night

Some roles require actors to learn martial arts. Others demand that they gain weight. To play the role of Father Christmas in the action-comedy Violent Night (out tomorrow), David Harbour had to do both.

"It was a very strange experience," the Stranger Things star tells EW.

In Violent Night, Harbour plays a boozy, depressed version of Santa who, we learn over the course of the film, has a very particular set of skills beyond being able to deliver presents around the world on a single night. When a rich family is menaced in their mansion by robber-mercenaries, Harbour's heroic St. Nick tries to save the clan's youngest member (Leah Brady) by taking on the villains in a very physical fashion. Before the shoot in Canada, Harbour had to transform his physique to look like someone who could beat the crap out of baddies while also being, let us say, cuddly enough to resemble a believable Santa.

"I put on about 70 pounds," explains the actor. "I was up in Winnipeg, I just needed the padding. I got real big for it and then I was also doing jiu-jitsu for months beforehand training for it. I wanted to do as much [of the onscreen fighting] as possible, and so I actually did a tremendous amount of training. The look that I wanted him to have was: big old strong Santa Claus. You'll see in the movie, I got big in all ways. I got a jolly old belly, but also, I got some shoulders and some other things that you don't see in the classic Coca-Cola Santa drawings. It was very weird. My movement was somewhat restricted because I had these big old love handles. I was with these [stunt] guys up in Winnipeg, and we would just go do crazy workouts, and then go eat poutine or whatever, out in the middle of Canada. So we were sort of like big old walruses."

This all sounds like the world's tastiest fitness program.

"Yeah, Jane Fonda, better watch your back." says the actor. "I think there's a whole industry there for me."

Violent Night is directed by Tommy Wirkola and co-stars John Leguizamo and Beverly D'Angelo. The film hits theaters Dec. 2.

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