In Mads Mikkelsen's new film, he's hammered most of the time. The story is a kind of crazy one, where Mikkelsen, playing a character named Martin, and three of his friends, all high school teachers, embark on an experiment to maintain a constant level of intoxication throughout the workday. Hilarity ensues, and so do lots of other complications. 

So how do you make a movie like this and act convincingly drunk? Mikkelsen told BBC Culture, "If you do one or two scenes in a film when you are supposed to be very drunk, you might have a beer to get the feel of it, but we were doing this every day for 60 days, so that would be a no-go. There were also days when we would be drunk for three hours in one scene, and then driving a car sober in the next. You can't do that if you've had a beer."

That's actually kind of genius. So how do you plan a shoot around the crew boozing? 

The movie was directed by Thomas Vinterberg, who was determined to find a level of realism within the story. To do this, he put them through an "alcohol boot camp." Actors spent two full days drinking on camera and then measuring their blood alcohol levels with digital breathalyzers. 

They used this to then inform their characters, studying how they would act on screen and knowing how they acted when they were actually that drunk.

Mikkelsen said, "If you're drinking yourself, rather than observing, it feels fine and natural if you've only had two or three beers. You don't see any signs of drunkenness. But if you're watching from the outside, you can clearly see and hear it in people's voices, the way they're a bit more loud, and the way they move a little more freely and loosely. At that socially acceptable level, it's just about little nuances, but the signs are there. When you're acting those scenes, you bring your shoulders down and you relax a little. I have a slight lisp, so I let that go a little, too."

When it comes to tips on acting drunk on camera, Mikkelsen didn't hold back. 

"Most actors will tell you that the secret of playing slightly drunk is to approach it as you do in your personal life," said Mikkelsen, "which is to try your best not to appear drunk. You move a fair bit slower, you're more cautious, a little more precise." The next stage of drunkenness is when "nobody's listening anymore, it's just people talking very, very loud."

But he encourages actors to stay sober when they are trying to get this into a movie, "Otherwise you wouldn't listen to your director, so it wouldn't work at all."

Ever act drunk on screen? Got any tips? Let us know them in the comments.