What's cool is that in the story of the movie [The Hangover] our characters are also really kind of getting to know each other and bonding over the course of the movie. And I think you're seeing a real, a literal sort of friendship growing both in us as actors and on screen as characters.

Improvisation is about finding the best joke or the silliest way to get something across. Improvising conflict is always fun because you can just go for it.

Let's just say it was damn hard [to make the Hangover]. I've got the bumps and bruises to show for it. It's funny because things that don't even look that bad on screen were still extremely painful.

I happen to think singing is hilarious, especially when it pops out at the wrong time.

I worked as an assistant editor, actually, for a few years. That was right when I was just starting to get out at night and do a lot of stand-up, improv, and sketch work in New York. It really is invaluable. I think it pounded into me an awareness of what an editor wants and needs, in terms of clarity of a moment, where and when to start and stop a line.

So long as your desire to explore is greater than your desire to not screw up, you're on the right track.

It's just one of those things like when you're not supposed to laugh, it makes it that much harder to stop laughing. And for some reason Zach [ Galifianakis] and I get in this feedback mood of giggling, and on the set of Hangover we just couldn't get through stuff.