So we've heard from Judd Apatow, Seth Rogan, Paul Rudd, and Katherine Heigl about their new comedy, Knocked Up. But what about their characters? Who are they really?

Katherine is the newbie of the group; she plays a newly-named E! News reporter/anchor, who's out to celebrate her promotion. She gets drunk, sleeps with Seth Rogan, and gets pregnant; it's then that the real fun begins.

Throughout most of the shoot, Katherine has to wear a fake baby belly; you would think for someone who's not used to having a real baby, it would be uncomfortable. However, it was just the opposite; she really didn't mind it. When we were on the set of Knocked Up a few weeks ago, she had just gotten out of the suit; "It's not that bad; it's pretty light, so it's not that heavy or anything and it kind of forces you to waddle a little bit, but that's probably a good thing, because it keeps you in character."

The only problem - it smells; "Yes, that only happens if the guys making them don't have enough time the night before where you have to dry it out properly and then you get it on you and it just smells rotten and it's awful and everybody around you is like, 'Oh, Kate's on set with her belly' and it's disgusting." The make-up crew has to design a new baby bump every day; that surprised me, and Katherine. "Yeah, I couldn't believe it; they make that thing every single day, and it looks so lifelike. It has veins in it. It's weird, it's bizarre, but it was fun."

Seth didn't stretch much to play his role in Knocked Up - except for the fact that he wouldn't have a one night stand. And this is really the first time Seth has had the starring role. "Yeah, definitely the acting schedule has been more intense and there's a little more pressure to come up with funny sh*t all the time. The script's very good and if I tend to fail in that, it's still pretty funny in the movie - I hope. No, I just hope I'm doing good; I've never done anything like this before really; it's really enjoyable and I really try not to think about it. That's my coping mechanism."

Paul's character is kind of going through a bit of changes throughout Knocked Up; he's a music executive, who is married to Leslie Mann (who is Judd Apatow's real-life wife) and has two daughters (played by Judd and Leslie's real-life daughters, Maude and Iris). "Guess that makes me Judd, doesn't it," he jokes. Paul's dealing with a failing marriage and his lack of self-worth. Leslie is Katherine's big sister in the film, so Seth and Paul become close friends after the unrepentant pregnancy. "I'm in my own little world of despair, getting older, settling down, having kids, being married - these are sacrifices that you make; there are amazing sides to it and then there are sacrifices you make."

Trying to keep things fresh for Judd is never a problem; as writer and director, he, along with Seth and Paul worked on the script and the story outline months before they started shooting. "Yeah, it's based on all of us, it's based on Paul and Seth; I mean everybody puts their distinctive stamp on these situations. I look at it as part of my Pat Robertson moral trilogy: The first movie is the anti-sex before marriage (Virgin), this is the anti-abortion movie. Soon it'll be the anti-Jew movie and then I'll realize I'm Jewish and get all confused. I keep making these movies and saying, 'wow they're dirty' but they have these really moralistic messages. How's this happening? They keep slipping in, so I basically try to make all these movies with the thought that they're about trying hard not to be an asshole. Any journey towards learning how to be a good person is funny to me, and what it takes to get there. I look at the movie as a story that talks about how hard it is to be married and to have children, but also how great it is and that it's a constant education in being an adult and doing the right thing, so there's a lot of my thoughts about those issues. And then, I would talk to Paul for a long time about his life and I know Seth really well so it's fun to tap him for all that."

And Paul and Seth know each other way too well; the two started talking about working on the improvised scenes in Knocked Up and just thought of funny situation after funny situation. Their conversation was so hilarious, I'll let you read experience some of it:

Paul started it off with, "I like doing comedies like this because when something organic happens, it can be so weird and funny. And just from a creative stand point, it's fun to go to work everyday because you don't know what the scene will yield. We have yet to actually - it's very rare that we film a scene exactly as it was written in the script; sometimes it'll go off into different directions. Like the one the other day - the whole Steely Dan run.

Seth Rogan: Oh yeah, that was so strange.

Paul Rudd: I play a guy in the music business, and we had no idea where everything went, and I was saying that a band like Steely Dan could never get signed today and they'd never get any radio play - and he says, 'That's because Steely Dan sucks.' And we get into this whole thing like 'no, Steely Dan is amazing, the early Steely Dan,' and you said something like 'I don't think you'd get into a Steely Dan concert without wine and cheese. If you ever catch me listening to Steely Dan, you could cut my head off with a Spiro Gyra record.'

Seth Rogan: Stuff like that; I liked that Back to the Future run. Me and Rudd are amused by very similar obscure referential types of things; we will degenerate any scene to us arguing about Back to the Future.

Paul Rudd: We both have the same kind of useless, encyclopedic knowledge of the most random facts or people. So no one will laugh, but me and Seth will just amuse ourselves; it's just burning a lot of footage.

Seth Rogan: We were just talking about how many people in the theater would get a Danny Pintauro reference - we don't think a lot.

Paul Rudd: Afterwards, we were like, 'Oh, why didn't we say that!' Then, we ran it by Judd and -

Seth Rogan: Judd was like 'Jesus Christ!'

Paul Rudd: It was Danny Pintauro with a thyroid condition. And we were thinking, if you actually said that in a movie theater -

Seth Rogan: Ten people would laugh very hard and no one else would laugh at all.

Paul Rudd: Yep, I think that's it.

Seth Rogan: Sometimes those ten need to be considered

Katherine knew walking onto the set of Knocked Up was going to be an interesting experience; and everyday is just "silly," she says. "What I like about Judd and his style is he's taking things stuff that everybody can relate to and relationship issues and hormone issues and kind of exaggerating it enough to be funny. But it's still honest and realistic and takes a very hard look at what it's like to be in a situation like this and make it work, and try to be responsible, and try to do the right thing, and try to be a grown-up because you're about to have a baby, but still being a child in a lot of ways. So I feel like it's going to be real funny; it's right up my alley as far as the humor goes, but it's also very sort of poignant and honest."

Judd has shot so much footage, executives from the Kodak company personally came to the set to thank him for supporting their brand. It's the second time that's happened - Judd received a similar honor during the filming of 40 Year Old Virgin. He feels getting every possibly second out of a scene is the most important thing; plus, a lot of that footage can be used on the DVD. "We always start with the extended DVD version in mind; unlike other filmmakers, we care more about our extended DVD version than the actual theatrical version, so we overshoot everything on purpose. Every scene that should be 20 seconds, we shoot an 8-minute version of; I can't even imagine the length of our extended DVD version. I said to Seth when I was editing [Virgin], 'Do you think we should just put back 4 or 5 minutes, or should we put back the 17 minutes?' And Seth said, 'Well, my dad always says, no one's ever mad because they get free sh*t!' This movie is a little bit close to your very edgy James Brooks movie than 40 Year Old Virgin, it doesn't have big comic set pieces, it's more character-driven, which may mean that the extended version seems insane - or you may just enjoy watching them talk and so what if I add another hour!"

We won't know how long Knocked Up is until it opens in theaters in August, 2007. Stay tuned to Movieweb for constant updates from the set.

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