A Long and Rambling Conversation With the Showrunner of Adventure Time

I’m a huge Adventure Time fan. The trippy cartoon that was marketed for kids, but seemingly made for stoned college students, premiered in April 2010, smack dab in the middle of my own college education. And by the time the series was coming to an end in the late 2010s, I was watching each new entry in the increasingly complex saga like it was a fresh episode of Game of Thrones. This was appointment viewing, often followed by A.V. Club recaps and YouTube analysis videos.

So when the opportunity to interview showrunner Adam Muto (who took over from creator Pendleton Ward during Season 5) came up, I leaped at the opportunity. And then, I panicked.

This long rambling preamble is basically an excuse for the fact that the below interview with Muto is more rambly than usual. We talked about the new spinoff series Fionna and Cake, but I also peppered him with some random Adventure Time questions that have been stuck in my brain for years. And sometimes I forgot to ask questions entirely and just shared my own thoughts on the show.

Hopefully, if you’re an Adventure Time fan, you’ll enjoy reading our conversation as much as I enjoyed having it. Also, consider yourself warned that there are some light spoilers from Fionna and Cake Episodes 1 and 2 in this article. So maybe watch the premiere first and then come back and read this afterward. I can wait.

Non-magic Fionna and Cake aren’t exactly loving life.


Hey, Adam! I’m a huge fan of the show, and I know that you’ve been a big part of Adventure Time. So I have a lot of questions. I’m trying to think where to start. I guess maybe just start by telling me a bit about how this one came together. And what was the impetus for doing it now with Max?

Sure. So when the original series ended, we had a couple of ideas that we wanted to explore potentially if they were interested in making more that weren’t just more episodes of the series. Even from early on, that list included Fiona and Cake, along with Princess Bubblegum, Marceline, and one more Finn and Jake thing. But Fionna and Cake didn’t make it into that first set of specials.

Then, when new management took over, they were looking at what we had presented and trying to find what felt familiar, but also new. Fionna and Cake perfectly fit into that slot because it had the recognizability of Finn and Jake, but it was an opportunity to do something completely different with them.

Originally, I pitched it outside and it took a different streaming service because Max wasn’t sure if they wanted to make more, and then we used that leverage to get Max to kind of pull the trigger on it.

Someone decided to print Ice King’s book. And he has fans.


That’s wild. Let’s really dive into Fionna and Cake. Every time someone turns on a TV in the Fionna and Cake universe, it’s playing Cheers. What are you trying to say there?

That was all a callback to Simon’s past with Marceline, where we had already established that he would sort of act out sitcoms that he remembered as entertainment for Marceline. One of the bigger Simon moments in the flashbacks was when he kind of tried to hold onto his sanity by singing the Cheers theme song. So this time we use it literally and see how that plays.

As he’s kind of stuck in this 20th-century mindset, we took it to an extreme and had Cheers being the only show in the normal version of Fionna World. But it’s not because Cheers has a deeper significance necessarily besides the kind of bittersweet theme song, which works really well in different contexts.

It’s also funny to me because at some point when he was a teenager, Tom Kenny [the voice actor who plays Simon/Ice King] just stopped watching TV. A lot of the TV shows that we would reference and theme songs that we’d have him reference he had no knowledge of. So we have this character played by Tom Kenny, who’s in so many shows, singing theme songs from shows he’s never watched.

Simon (Ice King) at the beginning of Fionna and Cake.


The voice cast in Fionna and Cake is pretty incredible. For one thing, Donald Glover is back as Marshall Lee.

He was just game to do it. They were all established voices so we just went back to everybody and saw if they were interested, but he was a surprise. I figured he would be the busiest out of everybody, but he really made time to be part of the show, and I appreciate it. I think he just does whatever he’s interested in. So it was really heartening that he would come back.

It was really a crapshoot. It was right after the pandemic’s heaviest days and production was starting up again. So all these projects that people had on hold were suddenly going. That’s why we had to recast a couple of parts. But getting Donald back especially was a big get.

Marshall Lee (Donald Glover) and Gary Prince (not Neil Patrick Harris).


Marshall Lee also plays a few original songs in the show, or at least one. Was Glover involved in writing those?

No. I mean, we had to get permission from his label and all that, but that would’ve been even harder. If I approached him and said, “Hey, can you write a song for us?” That would’ve been like another year of negotiating.

That was a song co-written by Patrick McHale and Somvilay Xayaphone that they had from years and years ago. They had a fake band with Pendleton Ward they had written a couple of songs. I think it was called The Bloody, and that was one of the songs they wrote for it. I could be conflating the fake bands they came up with over time.

Speaking of Pendleton, he also has a great voice cameo here as the male, non-magic version of Lumpy Space Princess, which I thought was hilarious. But did he contribute in any other ways? Did he have any influence on this story in this sort of sequel?

I’m trying to remember. I think we gave him a heads-up on what we’re working on, but at this point, he’s so concerned with his own projects that I think he’s happy to come back and do a voice. That’s sort of the limit of the involvement that he wants to have. We’ll see if in a couple of years from now we all need jobs. Maybe he’ll suddenly appear.

Adam Muto (right) with John DiMaggio, who voices Jake in Adventure Time.

Jerod Harris/Getty Images Entertainment/Getty Images

I’m sure you worked with him side by side for a long time. Is there any advice, anything that he ever told you that you still keep in mind when you’re working on Adventure Time?

I think this might’ve come from him. I’m not totally sure. But there are so many compromises in TV production because of your budget and your schedule that I remember him saying, “Try to find one thing that you’re really, really passionate about in each episode that’s unique to that episode, and make sure that that gets in. Because you can’t control so many things like how things are executed or how things are animated, but you can sort of narrow your focus to making sure one element of it turns out beautifully.” And I think that’s probably good for sanity. You’re never really finished. You just kind of run out of time on everything. So that felt like a healthy way to approach it.

Adventure Time creator Pendleton Ward (left) with the cast and artists of the show.

Amanda Edwards/WireImage/Getty Images

That’s really nice. I like that. Okay, random question: Is there a Prisma out there? A female Prismo?

I think not because the time room was sort of outside of that. But that was my thinking. I think in one of the supplementary books, they added a Prisma. But the way we present Prismo, it felt less consistent for there to be versions of him because he was at the very center and he was untouched by the things that he was doing. It was all sort of radiating outward.

Yeah, that makes sense. I guess also then he would’ve created his own female variant.

In that case. Yeah, that could be something he would do, actually, now that I think about it. But we didn’t think about including it in this series, at least.

Prismo has seen better days.


Fionna and Cake is doing a lot of different things, but in some ways, it does feel like a pretty close sequel to Adventure Time. You’re picking up a lot of characters a few years down the road and seeing what they’ve been up to. Do you see it as a sequel to the original series?

I mean, by definition, I guess so. You are getting appearances by those characters, but then most of the times you see them after the first cameo it’s as an alternate-universe version.

I guess we’re getting bits and pieces. We get a lot of Simon, but Jake…

Yeah. Jake’s current state is probably left the most mysterious out of everybody. But yeah, it definitely is in continuity. So you could think of it as a sequel.

Jake and Finn at an unspecified date.


I did want to ask about that. Maybe you’re keeping this close to your chest, but is Jake dead? And if so, do you know how he died? Do you know what happened?

I mean, if there’s a really simple answer to that, I don’t think it would be satisfying. We’ve shown Finn and Jake at the end of their lives. How it resolves. That’s the more important ending to me. You’ve shown them dead, basically. We don’t really show how Finn dies either. The how of it isn’t necessarily as interesting to me to show on screen because that’s kind of a downer.

So we left it ambiguous. It wasn’t important for this series.

“Canon is important to me internally when we’re working on a thing — that it makes sense — but I don’t expect anybody watching to really dig in and have the same level of obsessiveness.”


I saw I was doing some random internet Googling earlier today and I saw there’s a theory that Jake died from eating too much chocolate over the course of his life. It finally caught up with that.

Yes! See, if I gave a concrete answer, it would rob somebody of that. Exactly. I don’t want to just leave things open to shrug at them. But if it’s not answered in a story or left to the imagination, it’s probably not answered satisfyingly in like a comment or an article.

There’s a tendency sometimes to add answers after your series is done. But to me, whatever you put in is what’s speaking. So you can have your own theories, and I’m sure if you asked the people who worked on the show, the different board artists and writers, they would have different theories. I don’t want to cut those off yet or say definitively what the answer is.

That’s part of this series, too, dealing with the idea of what’s canon and what is meaningful to people. Canon is important to me internally when we’re working on a thing — that it makes sense — but I don’t expect anybody watching to really dig in and have the same level of obsessiveness. I think if you like the characters, you can do whatever you want with them and that is your version of it.

There’s so much obsessiveness about canon now and connecting things, and sometimes it’s franchises that have been around for 50 years and you have new writers coming in and answering old questions, and to me it’s like, well, that’s not the answer they had at the beginning. That’s definitely something they looked at and kind of came up with an answer for. But now that’s the official answer to it, which is a little weird coming this far after the fact after properties have changed hands three or four times. How’s that any more official than something somebody wrote their own?

The Ice Prince in Fionna and Cake, voiced by Brian David Gilbert.


Yeah, I think you’re right. But I’m still gonna try… So what about Finn? We do get a lot of Finn in Fionna and Cake. Would you consider doing a sequel about adult Finn’s adventures?

I think there are some other characters for sure that it would be interesting to do. Not discounting Finn, but so much of the original show was about him growing up that it felt satisfying where we left him off and now we’re seeing glimpses of him. He’s really unchanged and it’s not a clear line of getting more and more mature over the years. If there was a really good take on it, maybe we would do something. But I like the idea that he just kind of is living his own life and we get to see him, but we don’t necessarily have to follow him for multiple episodes. We kind of get around that by seeing the Farm World version of him, which is a very different version.

Eventually, there will just be some reboot that has nothing to do with the continuity we’ve established, and it’s more about the recognizability of the characters. Because they are very recognizable, just as visual icons. You have the blue thing and the pink thing and the yellow thing, and I feel like that might trump whatever particular character arc we laid out. It might become the new version and that will be somebody else’s Adventure Time.

“I think he might be out of the universe still telling Graybles.”

Cartoon Network

That’s a nice place to end things, but I’m going to ask one more question and then I’ll let you go as I’m out of time. One of my favorite characters, or sort of recurring things in the show, was Graybles. Those episodes are wild and I love them. So what happened to the Graybles character and do you think there will ever be more Grayble episodes?

Oh, that’s a good question. I mean, they were sort of hard to do after a certain point. We ran out of lists of five things. I think when we got to the hierarchy of needs, we were like, okay, we probably can’t do any more after this. We’re going to run out. The hidden theme idea might’ve reached its end, but we kind of do show what happened to Cuber in that one episode “Graybles 1000+” where he is kind of the focus of the adventure. He’s not dead at the end of that one. So I think he might be out of the universe still telling Graybles. What that episode did definitively say was that he lived in the future because Shermy and Beth’s world was contemporaneous for him.

But yeah, I don’t know about more Graybels episodes. I think we’d have to have more real estate because, in a 10-episode series, you don’t want to dedicate one to an anthology episode. I liked them. Graybels were one of my favorite things. And they were a favorite thing for the crew to work on because they were pretty short and you could get a bunch of different board artists on one episode, but I don’t know if those were the best-received episodes, ratings-wise.

Fionna and Cake airs on Thursdays on Max from August 31 through September 28.