Robert Downey Jr. is convinced that [movie id="461440"]"Due Date"[/movie] is a better movie than "The Hangover," for the simple reason that, as director Todd Phillips explained to MTV News, "Due Date" is about something, whereas "Hangover" just follows a bunch of groggy dudes around Las Vegas.

Phillips doesn't necessarily agree with Downey, but he'll take the compliment, just as he accepts the pressure of following up the $467 million worldwide success of "Hangover." His mission after that flick broke big last year was to get right back to work. For that task, he hauled Zach Galifianakis back into the mix and recruited Downey. "Due Date" follows Downey's character, Peter Highman, whose wife is about to go into labor, forcing him to hitch a ride with Ethan Tremblay (Galifianakis) in an attempt to get to the hospital before his child is born. Their road trip does not, to say the least, go smoothly.

As part of MTV News' ongoing Fall Movie Preview series, Phillips called us up to chat about working with Downey on a straight comedy, the "anti-chemistry" of his two stars and the difficulty of pulling off a cinematic stunt as surprising as the naked Asian who jumped out of a trunk in "The Hangover."

MTV: I take it you've locked picture a while ago, right?

Todd Phillips: Yeah, we have. This movie could have come out in the summer, but because of "Iron Man 2" and Robert's press requirements for a movie that size, we had to space them out.

MTV: If it's been done for a while, do you ever wake up and say, "Crap, I need to use a different take! I should have done this differently!"

Phillips: It's funny you say that, because just yesterday we watched one of the release prints at the Arclight [theater in Los Angeles]. You want to see how the prints look, so you go to a regular theater. There was actually a little sound issue. So we went back in and fixed something with the sound. But that was more of a technical thing than a creative choice. When you look back at movies, you always go, "God, I would have done that differently, or I wished we had tried this," but this one is still too close for me to do that.

MTV: Right, it's when "Road Trip" comes on TBS that you go, "Damn!"

Phillips: Right. I'll see "Old School" sometimes on TV and I'm like, "Oh, if only we'd had more time that day we could have done that better."

MTV: You do have this great history with Warner Bros. and you're coming off the huge success of "The Hangover." When you said you wanted to do "Due Date," were they ever like, "Todd, man, maybe hit 'Hangover 2' first?"

Phillips: You know, being at Warner, not to sound like a corporate kissass, but Warner Bros. is like being on the Yankees.

MTV: I'm a Mets fan, my friend.

Phillips: It's still like being on the Yankees! They just have it so wired. The filmmakers that they choose to work with they support wholeheartedly, as evidenced by gambling on a movie like "Inception," which was so brilliant but so big a gamble in studio terms. But they trust Chris Nolan because he's f---ing amazing and they just let him do it. It's pretty much the most supportive studio I've ever been involved with. They were excited to do "Hangover 2," but once I had spoken to Robert Downey about "Due Date," they totally got it.

MTV: Getting someone like Downey, does that alleviate some pressure -- if there is any -- about following up such a massive hit?

Phillips: I think pressure is always a good thing. A lot of guys make a big hit movie on the size of "The Hangover" and they get gun-shy. They wait a few years in a weird way, and I wanted to do the opposite. I wanted to do something again and not worry if it was going to be as big as "The Hangover" because "The Hangover" was lightning in a bottle. You can't judge other successes or other movies based on it. I just didn't want to get into that headspace. That was part of the reason for striking out and doing something real quick like "Due Date." It's something I had been developing -- it's not like it's rushed -- but it went quicker because I was like, "Let's just go do it." For me, I choose movies based on who I can get in it. Comedies are so about casting. Obviously I wanted to work with Zach again after "The Hangover" and Downey is pretty much the best there is out there. Once he said yes, we were like, "Let's just go."

MTV: We haven't seen Downey do much straight comedy in a long time. I guess you could say "Tropic Thunder," but that's hardly something typical and straightforward.

Phillips: Yeah, you haven't seen Robert Downey be Robert Downey. A lot of great actors -- you see this with someone like Johnny Depp, who's a huge f---ing talent, and Robert Downey -- where they play parts where they're putting on masks or accents or hats and wigs. They kind of like to lose themselves in a role. In "Tropic Thunder," which I think is great, he's in blackface and you're not really seeing Robert. What was fun for Robert about this, and what was fun for me to make it, is Robert Downey just being Robert Downey. There's no makeup, wigs. It's just Robert playing such a real character.

MTV: Was that one of the reasons he signed on, to get back to something with less artifice?

Phillips: I'm not sure why he makes his choices. I know he loved "The Hangover." I know he loves Zach and was a fan of my films. Actors like to play. For a guy like Downey, he loved the idea of not being on a green screen for 60 days and just coming in and f---ing around with a guy like Zach and a guy like me. It's a real loose environment, as opposed to something like "Iron Man 2," just by nature of the effects.

MTV: A movie like this lives and dies on the chemistry of those two dudes.

Phillips: Or the anti-chemistry, in this case. It's interesting, because before "The Hangover" came out, people could dismiss it or say, "Oh, it's a movie about bachelor parties and Vegas. I've seen that before." And a movie like this, you go, "Oh, it's two guys on the road. It's 'Tommy Boy' or it's 'Planes, Trains and Automobiles.' " And it's really not. It works on this whole other level that I think people are going to be surprised by. It connects on a different level.

MTV: It's probably hard to put into words what that level is, but what were you aiming for?

Phillips: This is how Robert explains it, which is sort of a backhanded compliment. He goes, " 'Due Date' is a better movie than 'The Hangover' because 'Due Date' is about something." I know what he means. There's another dimension. As proud as I am of "The Hangover," it's a two-dimensional film. It's a comedy that works as good as any comedy could work. But there are some character moves in "Due Date" that Robert and Zach go through that I think will be surprising on a film that you think you have figured out by the trailer or the poster.

MTV: You mentioned that people look at it and think "Planes, Trains" or "Tommy Boy." Did you go back and look at any of those road trip movies for inspiration or in terms of what to avoid?

Phillips: I love "Planes, Trains," and I seriously love "Tommy Boy," which is one of my favorites. But one movie all three of us looked at is "Midnight Run." That might be the best of the bunch. It's not so much to emulate or avoid, it's just to be inspired in some way. "Midnight Run" was a big one for me.

MTV: The Dan Band has popped up in a bunch of your movies. Any chance we're going to see them in "Due Date"?

Phillips: The Dan Band is not in "Due Date," and it's just by the nature of what the movie is about and where it winds up. There was no way without it feeling incredibly forced. But you could argue it's a little forced in "The Hangover." But I love them so much. They're the best.

MTV: I don't know if this is one of those questions you get a lot, but where do you go from a naked Asian man jumping out of a trunk in "The Hangover"? How do you top that?

Phillips: That is a tough one to top. The key with comedies in general is they work when there are surprises. So a naked Asian man jumping out of a trunk is a perfect example of a surprise. It goes back to what I was talking about before with even just the nature of "Due Date." There are a lot of surprises in the film that I think take the movie to another level. The surprises won't be a naked Asian man or the Dan Band, but I think there are enough surprises that it will connect with people. But that is the challenge, because comedies work so well when they are surprises.

From the saucy Jessica Alba in "Little Fockers" to James Franco's grueling journey in "127 Hours," the MTV Movies team is delving into the hottest flicks of fall 2010. Check back daily for exclusive clips, photos and interviews with the films' biggest stars.

Check out everything we've got on "Due Date."

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