We played around and improvised a ton [in The Hangover], and I think it's hard to say at this point what's what. Gosh, I wouldn't even know how to take a stab at it. The script was so good that we really didn't need to improvise very much, but I think we just found a lot of moments on the set. It's really cool when you get onto the set of a movie and you start shooting the scenes and you start to actually incorporate the environment.

Vulnerability is huge. I love to see that in characters. It's something I feel like a lot of my comedic heroes have always done.

When you're playing a fictional character reacting to the real world, it's incredibly difficult and confusing and kind of messes with your values a bit.

When you try hard at everything you do, even when it feels foolish to do so, you’re opening up doors and possibilities you might not be seeing in the moment.

We spent six weeks there [in Vegas]. The only thing crazy that I did was shoot that movie [The Hangovers]. The stuff in that movie is way crazier than anything I might have done, drunk one night in Vegas. I mean we did it for real in the movie, so that's as crazy as it got.

I'm sort of laughing and so Zach [ Galifianakis] started laughing [on the set of The Hangover]. And Todd [Phillips] was baffled because what we were saying wasn't that funny, you know what I mean? And it was like all the baby's face. So Todd was like, 'What is going on? Get it together guys.'

The improv stuff, that's always surprising so a lot of times that's really funny.