“It’s one of those things where I can’t even believe I’m in this movie.”

It’s very late on a Sunday night and Bill Hader would probably rather be somewhere (anywhere!) else. It’s his 37th birthday and instead of spending time with his family (wife, writer and director Maggie Carey and their three children), he’s sitting inside a hotel room promoting a movie. But, if you’re going to spend your birthday with a stranger, you might as well be talking about a movie as wonderful as Inside Out.

The latest from Oscar-winning director Pete Docter (Up) could very well be the best film Pixar has ever made (a lineup that includes seven Oscar winners for Best Animated Movie and two nominees for Best Picture). Hader is too close to the film and it’s creators to confirm that sentiment (“It’s definitely the best one that I’ve been in!”), but the self-professed “Pixar nerd” can admit that Inside Out is “a very special movie.”

In addition to supplying the voice for Fear, the neurotic and anxiety-driven emotion inside the brain of 11-year-old Riley, Hader has also been spending time inside the Pixar writer’s room, where the so-called Brain Trust convene to work out their upcoming movies. The former SNL star (who also has a cameo as the running slug in Monsters University) has been making recurring trips to the Emeryville campus to contribute to the story process, similar to his role as a Creative Consultant on South Park.

We spoke to Hader about working with (and for) Pixar, his contributions to their movies and why, even though he was cut out of the film, he still thinks The Good Dinosaur is going to be awesome.

All the other actors, their personas match their characters pretty closely, but when I think of you, I don’t initially think of fear or anxiety.

Well, I’m friends with those guys [at Pixar] and I am a pretty neurotic person. Before every SNL, I would basically have a panic attack, so that could be it. I’ve never asked them why. They just asked if I wanted to play Fear and I said YEAH!

Did you become friends with the Pixar guys through Monsters University or —

No no, I sought them out. I’m a big Pixar nerd. So I asked if I could go to Pixar and meet them. I went and met those guys and then they came to SNL and watched how we work. They returned the favor and I went to Pixar and hung out and watched how they work. Then I was hanging out in the writers’ room in the story department for a week and that became a reoccurring thing. Every six or seven months, if I had time in my schedule, I would go up to Berkeley and just hang out.

Are you hanging out in the story room like a fly on the wall, or are you an active participant?

It was active. It’s basically the way I am at South Park. I’ll pitch things every once in a while, but usually you’re going, “That makes sense to me,” or “That doesn’t make sense, can you explain that?” Or, “That does or doesn’t work for me because blank.” But, I’m wrong a lot too. I remember I didn’t like the personality islands at first.

Why?

I just didn’t get it. We were in Pete’s car and I had the fucking balls to be like, “Pete, I don’t understand the islands.” And, he was polite going, “Yeah, I get ya, but I want to try it.” Then, I saw the movie and was like, “Oh my god. I’m a fucking idiot.” He explained it would be good because it gives real stakes to what’s happening. We had no stakes.

There’s no villain.

Right! There’s no villain, so we had no stakes to what’s going on inside her head. There’s no, “Oh my god, we need to hurry, because there’s a ticking clock and these things are happening!” And, then he thought about what that could be that would work on a couple different levels and the personality islands was the choice.

Bill Hader in the Pixar writers' room with director Pete Docter and producer Jonas Rivera / Pixar

Was there anything you’ve pitched in the writer’s room that has made it into a movie so far?

Ummm, one thing I pitched that we ended up doing was the part where Fear says, “I’m gonna take the coward’s way out,” and he gets stuck.

As a huge Pixar fan, it must be mindblowing to see a character modeled after you. It’s not like you’re just voicing a character, Fear’s physicality is very much based on your performance.

Yeah, I know. They’re videotaping you while you’re recording. And you’re performing, really. You’re using your whole body as you’re recording. It’s a lot of fun. I was so impressed with the way they did. And, they take so much time. They really care.

Did you get called back a few times?

Yeah, I did a bunch. You go and record and go back. I recorded a lot over the past four years.

Pete Docter has admitted that an early cut of the film just wasn’t working. Did you ever get a sense for what wasn’t working and what they did to fix it?

I can’t remember. [Long pause] It went through so many permutations. I remember when they first pitched it to me, it was Fear and Joy who were on the journey together. And that Riley was running away from home and gets knocked out. She slips and gets knocked out and the whole thing takes place as she’s passed out in the woods. I remember them pitching that version to me, and I told them, I don’t really care about what’s going on inside her head, because she’s passed out in the forest and I’m just worried about this poor girl. And they went, “Yeahhh, that’s a bad idea.”

I should also say to their credit, there’s a lot of things that Pete and those other guys changed that a lot of other people would’ve said, “OK, this is great, no problem.” They remind me of the South Park guys in that way where they’ll say, “No no, we’re not just going to run off and do this, we’re going to make it right.” And, they know that part of doing their job right is to sit on something for a little bit and to think about it and ruminate on it and then go back to it. They’re very intuitive. Pete will always say, “That doesn’t feel right”. He’s never saying, “The Act 2 reversal is...” or “the midpoint is on Page 60, so this needs to happen”. He’s not like that. That’s never part of it at all. It’s always following the logic and emotion of the characters and the story. It’s the same way with South Park.

With this movie and The Good Dinosaur coming up, have you had talks about staying on and contributing to future projects?

I should say that I recorded something for Good Dinosaur two years ago and I don’t know if I’m still even in it. [Late last week it was confirmed by Disney that the majority of the original voice cast, including Hader, had been replaced.]

That’s a good example of what you were saying about Pete and Pixar. They’re not afraid to make those changes.

Yeah. I don’t know if I’m still in it, but I know it’s gonna be awesome because all my friends over there keep telling me how great it is.