Dan Harmon and Justin Roiland tell THR about the difficulty of living up to their own expectations for the show: "We're beating ourselves up for no reason."

The creators of Rick and Morty still need to remember at times to enjoy themselves while working on the show.

The Adult Swim animated series, which was recently picked up for a third season, airs its season-two finale Sunday, continuing the intergalactic travails of awkward teen Morty and his grandfather Rick, an alcoholic inventor.

Co-creators Justin Roiland (who voices both title characters) and Dan Harmon spoke to The Hollywood Reporter about how a serious case of writer's block, followed by a middle-of-the-night breakthrough, taught them that making the show "doesn't have to be difficult."

They also discussed how the third season will differ dramatically from the first two, the latest on their side projects — including Harmon asking Roiland why he wasn't invited to help with one potential series — and why their previous interview with THR may have helped bring the first female writer to the show's staff.

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Before the season started airing, Dan said that the season would provide viewers' best and worst episodes. How are you feeling now that the season is wrapping up?

Roiland: I've been surprised with the reactions across the season. We went into the premiere thinking the first episode was going to be received poorly, and it wasn't, and then I think that trend has just kept going across the season. It's definitely not for lack of our hard work and trying to make it as good as we possibly could. I think, if anything, we're just our own harshest critics, so we're beating ourselves up for no reason. (Laughs.)

What are you most proud of about season two? Which moments from the season stand out to you?

Harmon: My favorite moment of the whole season is in the inter-dimensional cable episode where they're in the hospital and [writer] Dan Guterman's joke — just the nano-doctor. They cut the patient open, and then the doctor says, "Nano-doctor." (Laughs.) And the nurse hands him a tiny doctor and says, "Nano-doctor." And then the nano-doctor says, in my falsetto voice, "Nano-scalpel." And the nurse hands him a tinier scalpel. And then the larger doctor seals the surprisingly-large-for-a-nano-doctor in the chest of the patient. They're aliens, so I guess they know what they're doing.

Roiland: (Laughs.) I do love that moment.

Harmon: I had nothing to do with it, and I think, [like] at Community — which I almost never bring up in these interviews — it starts with pride at creating something, in this case with a good friend and collaborator, but again, one of the biggest joys of doing more episodes was hiring people that get the show because they've seen it on TV, and they're coming in and going, "What about this joke or this idea?" And it's like, "Wow, this is better than just making something cool." This is as close as I'll get to giving birth to something that's now walking around.

Roiland: I have two that pop into my mind. One of my favorite moments was the very ending scene of the Purge episode — it's a bunch of guys standing around, and they're trying to figure out how to reestablish the society. Every time I watch that scene, I laugh — just the specificity of [Rob] Schrab's voice performance, and then Dan going, "Whoa, whoa, whoa, whoa — guys, guys! Take it easy!" The other thing is the "plumbus" [how-it-gets-made] thing — I'm just so happy that exists.

Harmon: That's a masterpiece. You mentioned that Purge episode — I think that's the biggest lesson I learned from season two. It took almost the entire season's worth of prep time to write the first episode. And then the Purge episode, it literally took just as much time for me to type the first three-quarters of that episode as it did to watch it. We had a nervous breakdown — we [wanted to do] a two-part finale. So we wrote the first part of the finale [which will air as Sunday's finale] — this is how the sausage gets made. I've de-romanticized our process.

Roiland: (Laughs.)

Harmon: In trying to write the second part [of the finale], we just couldn't write. We were just blocked and exhausted. It was three o'clock in the morning, and I said, "What about this f—ing Purge thing we keep talking about? Let's just do that." And [writer and voice castmember] Ryan Ridley was like, "Well, we can't start writing a new episode now that we've spent all this time trying to break the story for this thing," and I was like, "No, we can." And in a fit, I just started jamming out this thing, almost sarcastically writing an episode, which is really how we wrote the pilot. It was a couple hours of us just sitting on the floor with our laptops — we split a Ritalin, and then we wrote the pilot. (Laughs.) We took every other scene. The show doesn't have to be difficult for us.

Not to make this an issues interview, but when we spoke just before the season-two premiere aired, you said there weren't currently any female writers on the staff. Is that still the case?

Roiland: It's funny that you say that. It hasn't been an agenda thing, but just coincidentally for some reason — I don't know why — this staffing round going into season three, we got a lot of female scripts in addition to male scripts. We just look at what's the best script — I think in the running, we have five or six girls. It's weird — that's never happened before.

Harmon: I think the last time you asked us about it, we made a self-deprecating joke about it and moved on because we didn't want to make the whole interview about that issue. I remember when the piece ran, I got tweeted by nine or 10 young gentlemen who were lambasting me for not taking the issue seriously — not a single female writer tweeted me and said, "You shouldn't have joked about that — you should have apologized to America and promised to hire a woman." I like to think maybe that article ran and a bunch of great female comedy writers sat down and wrote specs or called their agents and said, "Put my hat in this ring." [But] the day there is a female writer in that writers room, that person is definitely not going to be thinking that they're a quota writer.

Roiland: Anyone who makes the cut and joins the team has definitely done so on their own merits. We've gone from having zero spec scripts [in the running from female] candidates, to having five or six of them, so it's looking very likely that season three will have one, potentially two gals in the room. I think it will be fun and interesting.

Harmon: And this is where I say something like, "It'll be great because the writers room could use new curtains." It won't play in print — send your tweet about my curtain joke that I didn't make to @DanHarmon.

Roiland: We'll all be eating better meals. Our clothes will be clean.

Harmon: The truth is, the writers room on Community, when we specifically decided, because we had a self-imposed and imposed mandate, to do a perfectly balanced writers room gender-wise — which you can accomplish with network TV with a budget that size, visibility that high — [Community producer Chris] McKenna and I did notice that the writers room started to smell better. But I think it was because the guys got ashamed and started cleaning up their garbage a little bit more, probably unconsciously.

What's the latest on your side projects? Justin, is Solar Opposites [the outer space animated show that he tweeted about being in development at 20th Century Fox] a real thing, and Dan, what's the news on your IFC pilot [Great Minds, a comedy panel show that he's hosting]?

Roiland: I still haven't pitched [Solar Opposites] to the network — I leaked [images on Twitter] as a joke. It is a real project [being developed with Rick and Morty's Mike McMahan]. There's not too much to say other than, it's the old development wheel. It will probably go to pilot, and then it will be my job to write a script.

Harmon: (To Roiland) Hey, can I ask you? We've never discussed this, me and Justin — I will ask you in front of The Hollywood Reporter and with the world watching. Why did you not come to me with this idea?

Roiland: (Laughs.)

Harmon: You wanted to have your own thing? And also, I have an animation studio.

Roiland: Well, two things. There's no studio attached — no animation studio. And the second part of your question — you're a busy dude! You're stretched thin.

Harmon: I don't have to be. I'm busy because I'm getting old — I want a nest egg. I want to provide for my family and my kids that aren't born yet. If I had one conversation with you, it would save me five meetings with a wider net that I'm casting. But anyway.

Roiland: Jesus Christ. Let's get together very soon, in all seriousness.

Harmon: Well, duh-doy.

Roiland: (Laughs.)

Harmon: Don't make me have to do this in front of The Hollywood Reporter next time.

Roiland: (Laughs.) And then, Harmon. Your IFC stuff — I'm curious about that, too. (Laughs.)

Harmon: I had heard that IFC liked what we shot. I watched the cut of it, and I thought they could do with a better host. My stutter — it's very charming on a podcast, but it was untelevisably [bad]. It's like, "Oh this guy's got a real problem. This is like King's Speech-level stuff. Someone's going to win an Oscar portraying this guy one day, but he should not be on TV." [But] that's the update — [IFC evp of original programming] Pete Aronson said it was great, so we'll see.

As Rick and Morty continues its success and you both get other opportunities, will you perhaps become less hands-on with it?

Roiland: No. We really have an opportunity to grow this thing and make it insane — we have a real thing in our hands. It's just exciting to see that people love it still — it keeps growing and growing. That's going to be a big priority above anything else, for me anyways. Not to get too inside, (in mischievous voice) but obviously there's going to come a time when can renegotiate our contracts, and if the show's still really successful, we might be able to get a lot more money, and all that stuff.

Harmon: (Jokingly cutting him off.) All right.

Have you started to think about where season three is heading?

Roiland: I've been jotting ideas down, yeah. Nothing super fleshed out, but there are definitely little seeds.

Harmon: I rewatched both seasons a couple nights ago, and now I'm excited about revisiting stuff in season three because I was so phobic about revisiting stuff in season two. Now, we can fade in on [arcade] Blips and Chitz because we've already proven that the show isn't going to start eating itself, and that will feel even more limitless if we go back to a couple things that we really enjoyed doing.

So Mr. Meeseeks may pop up again in season three?

Harmon: I'm going to make that a personal promise to myself. (Laughs.) I'm going to force Mr. Meeseeks into season three.

Rick and Morty's season finale airs Sunday at 11:30 p.m. on Adult Swim.