(Cover) - EN Showbiz - Zach Galifianakis says whenever he tries to be serious a four-year-old comes out.

The 41-year-old actor is best known for playing kooky Alan Garner in the smash hit comedy The Hangover, about a group of friends who experience a wild night out when they go to Las Vegas for a bachelor party.

As his hilarious acting roles suggest, Zach loves goofing around and making people laugh, although he insists he does have a more sensible side. Zach admits his serious nature isnt often displayed though, because he cant stop himself from being silly most of the time.

I try to be serious but usually the four-year-old comes out and its hard to be... its a hard mix, he told the BBC.

Zach has been praised for his performance in the comedy drama It's Kind of a Funny Story, which tells the tale of a clinically depressed teenager who checks himself into an adult psychiatric ward.

The actor says it was important for him to star in something which wasnt such an obvious or stereotypical comedy, as after The Hangover he feared people would only see him as a mainstream wacky actor.

This movie is something I wanted to do rather than just being the fat bearded guy in an over-the-top comedy, he explained.

The star understands movie producers and critics will try to pigeonhole him, but he doesnt want it to go to the extreme. Zach believes he has far-reaching acting abilities, so he is paying extra attention to his movie choices.

The nature of the Hollywood machine, thats what they want you to do. You have to be cautious of that, I think, he replied when asked if he was worried about being typecast. (C) Cover Media