Credit: Paramount Pictures

In 2007, Jason Reitman directed Juno, about a young girl who talks like a 30-year-old. Four years later, he and screenwriter Diablo Cody re-teamed for a movie about an adult who acts like a child. Young Adult, the scorchingly caustic comedy about a teen-lit author (Charlize Theron) who returns to her hometown, hits DVD and Blu-ray today, so we spoke with Reitman about making the film, casting Theron and co-star Patton Oswalt, and that more-bitter-than-sweet ending.

ENTERTAINMENT WEEKLY: When did Diablo Cody first show you the script?

JASON REITMAN: We finished the movie a year ago, and she showed me the script probably the year before that. I loved it and we knew that if we were going to make it, we’d have to make it quick. Diablo and I sat down to do a one or two week high-speed polish and by the end of that process we did a table-read of the script, and basically I finally hung my decision on whether or not Charlize would say yes.

So it was Charlize or nothing?

Yeah, it was literally Charlize or bust.

Did she take any convincing or was the script enough?

When she first read it, she wanted to make sure our vision was clear. It’s a very tricky film that all balances on her ability to play that role. We had already spoken and met and were fond of each other and wanted to work together, but this is the kind of role where the actor really has to trust her director because she could totally be left hung out to dry.

Young Adult almost seems like the anti-high school reunion movie. There’s very little nostalgia for the good old days.

I guess so. People ask me a lot about high school and I never really think about high school. And I never think of this movie in terms of high school. For me, this is a movie about people in their 30s and it’s about questions like, “Can we change?”, “Are we incapable of change?”, “Who do we become?”, “At what point do you give up?” These kinds of ideas, which are much more important to me.

The ending is pretty emotionally complex. Did you and Diablo struggle with it?

Struggled? Not for a heartbeat. That’s the entire reason I made this movie, the ending. The script, the first two acts of the script are very good and are very well written, but it’s the third act that makes it great, and when I read that third act I thought, all right, I need to make this movie. I was very fortunate that Paramount never asked me to change it or to do anything different with it. Those last three scenes, those were the reason to make the movie.

It almost has the structure of a happy ending, but once you look at it below the surface, it’s remarkably unhappy.

All my films use devices to make the audience feel like they’re watching one type of movie but in reality they’re being drawn towards something else. Young Adult, just like Up in the Air, is meant to make you feel as though you’re leaning towards the moment where the character is going to see the light and change like every other film character does, and it’s by virtue of taking the audience down that road that it truly hurts once you get to that ending.

Music, particularly a Teenage Fanclub song, plays a large role. How did you go about incorporating it into the film?

I’m fortunate that when I work with Diablo she writes a lot of music ideas into the screenplay. She tends to do that across the board: She writes wardrobe and production design in, too.Her screenplays are very, very directable. On the music side, I think Teenage Fanclub was just the perfect choice and I just ran with it. Choosing music is like anything else in film: It requires a good ear.

Patton Oswalt gives a great performance as Mavis’ friend-slash-Jiminy-Cricket. How did he get involved?

We did a table read of the screenplay at my house and Patton came and read the part of Matt at the table read because he’s a friend of mine. And it was just perfect. Then we tried it with Charlize and they had such good chemistry that it was a no-brainer to bring him on.

Matt’s a bit of a self-identified geek, and so is Oswalt. Did he bring his own brand of nerdiness to the character?

I think Patton’s just a great actor. He understood the vulnerability of that role, he understood he was the voice of honesty in that movie. What he didn’t know, and I didn’t even know this until the film was done, is that he becomes the person that the audience watches the movie through.

Did you ever feel like you needed to pull back some of Mavis’ nastiness in order to make her more relatable? Like, “This is a bit too much?”

I don’t think of her as that nasty in the film. Maybe I’ve got my own issues. I find her as vulnerable and sad and interesting, and I understand why she’s saying all the things she does, and frankly I’d probably been more interested spending time with Mavis and Matt than I would with Buddy and Beth, who are kind of boring.

Last question: You’re currently working on a movie called Labor Day. I’m guessing this isn’t an unofficial sequel to Valentine’s Day and New Year’s Eve, right?

What do you think?

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