After a long 10 years, creative geniuses Dan Povenmire and Jeff “Swampy” Marsh are bringing Phineas and Ferb back for another 104 days of summer vacation. The beloved cartoon aired on Disney Channel from 2008 to 2015, with Povenmire voicing the evil Dr. Heinz Doofenshmirtz and Marsh voicing his arch nemesis (and Perry the Platypus’ boss) Major Francis Monogram. With the long-awaited fifth season finally airing this week, DECIDER caught up with the two men behind the iconic series (and its two spinoff movies).

The first four seasons of Phineas and Ferb follow the adventures of two stepbrothers with one goal: have an epic summer vacation. They build roller coasters, backyard beaches and portals to Mars, while their older sister Candace (Ashley Tisdale) does everything she can to rat them out to their often-absent mother. At the same time, their pet platypus Perry doubles as a secret spy who sneaks out each day to foil Dr. Doofenshmirtz’s evil plans to conquer the tri-state area.

While Season 5 marks the start of a new summer for Phineas and Ferb, the show’s creators didn’t want to change anything about the already successful series.

“What we hope is that people watching the fourth season on Disney+ could just go right into the fifth season [and] they wouldn’t notice it,” Povenmire said when he stopped by our studio. “The only thing we changed in the characters is we put an extra stripe on Phineas’s shirt because it’s a year later.”

Aside from Phineas and Ferb being a year older, fans can also expect some exciting guest cameos this season, including Ted Lasso stars Brendan Hunt and Cristo Fernández.

“They occupy a very similar space of positivity in the world,” Marsh said. “When I started watching [Ted Lasso], I originally said to my wife, ‘This is kind of the live-action, spiritually and emotionally, the live-action version of our show.’ It’s really good-natured at its core.”

Povenmire and Marsh also talked about Phineas and Ferb’s TikTok fame, the catchy musical numbers, and Linda’s (Caroline Rhea) shocking disappearance in the premiere episode. Check out the full interview below.

DECIDER: I’m so excited to have you guys here, especially since Phineas and Ferb was such a big part of my childhood. It’s been 10 years since the show went off the air, so why was now the perfect time to bring it back for Season 5? 

DAN POVENMIRE: Because they said they would pay us money.

JEFF “SWAMPY” MARSH: Yeah. They called and said, “Would you make more?” And we were like, “Yeah. Best job we ever had, duh.” The truth is – and Dan said it before – during COVID, it really got a lot of streams on Disney+ because it was sort of a comfort watch for people. They realized that the show never really lost that much popularity over all these years. Somebody probably asked the question, “Why did we stop making those?” And probably, without anyone giving a reasonable answer to that question, they said, “I don’t know. Call them.”

Is it true that you guys came up with the concept and characters for Phineas and Ferb in 1993 – 15 years before it premiered on Disney Channel? What does it mean to you that they’ve held up for so long? 

SWAMPY: It’s gratifying that we continued to pitch that show in spite of all the nos we got to find out that we were right. 

DAN: Yes, exactly. I like when we’re proven right and everybody’s proven wrong. It’s been so great just realizing there’s still so many fans out there for it. I think that when the show stopped, we just moved on and made another show and there’s always a special place in my heart for this show. And I don’t think I realized until TikTok – I got on TikTok and I did one video where I talked like Doofenshmirtz and it got millions of hits and I was like, “Oh, my gosh!” I started just scrolling through TikTok and I would look for Phineas and Ferb stuff and just the amount of people still talking about this show made me feel like, “Oh, this is really…” It felt great. 

That actually leads into my next question. There’s one particular Doofenshmirtz quote that is always being used on TikTok and that’s the “if I had a nickel for every time this happened…”

DAN: A friend of mine is a college professor and for years, he’s been hearing people say that thing. [In Doofenshmirtz’s voice] If I had a nickel for every time blank, I’d have two nickels, which isn’t a lot, but it’s weird that it happened twice. 

He texted me like a month ago and said, “Oh, my gosh, Dan. I just found out that this thing that people have been saying in my classes for years is a quote of you.” I love that. It’s sort of become part of the pop culture.

It totally has! It must be so cool to hear your voices in these TikToks.

DAN: It’s really strange.

SWAMPY: It’s very interesting, but it is really weird.

Pretty much the entire original cast is returning for Season 5, including the both of you, Ashley Tisdale, Caroline Rhea, Alyson Stoner, etc. Were you guys the one to make the calls to the cast to pitch a new season? And what were all of their immediate reactions? 

DAN: There’s some of them that we were still in touch with and so I think I mentioned it to most of them. But casting is the one that made the official call.

SWAMPY: I mean, I’ve been working on different shows that we’ve gone on to produce. We’ve been working both independently and together. We’ve been hiring all of those people to come back and do voices for us because we love working with them. The kids have grown up right in front of us. 

Ashley’s a mom now – and she’s been posting videos of her daughter singing along with her songs from High School Musical. I also heard she brought Jupiter to a recording session for Phineas and Ferb. As two people who have known her and worked with her for nearly two decades, what’s it like to see her in this mom role?

DAN: It’s great. It’s really great, because I think she’s a great mom. I ran into her and her husband at Disneyland the other day. I saw her husband, who I know, but I haven’t seen him a lot. I saw this guy come in, and I was like, “I know him. How do I know him? Oh, he looks just like Ashley’s husband. Oh, there’s Ashley. OK, this is him.” It was the first time I’d gotten to meet Jupiter. I’d heard about her having the baby. And it’s just so great to see her in that role. I think she fits in it really well.

SWAMPY: It does make you feel…

DAN: A little bit old … She was at least adult-ish when she started, right? She was a young adult as opposed to Phineas, who was 12 or something when he started. Now he’s over 30, he’s got a beard. 

SWAMPY: We’ve been having people both internally and externally posting all these old pictures, old publicity, and you realize just how dark my hair was. 

DAN: Yes, exactly. There was none of this, there’s none of this. We look pretty much the same, just we look like very young versions of us. 

SWAMPY: Just colored with a different coloring box. 

Phineas and Ferb have invented a lot, from time machines to giant gelatin molds to s’winter. What inventions were you each most proud of or excited about sharing with the fanbase?

DAN: To me, the quintessential thing that they built was the roller coaster. That was just the perfect thing – what would two nine-year-old boys get up to if they could do anything? 

SWAMPY: Build a roller coaster. I’d still do that.

DAN: Later, they just redid the whole same day as a as a musical, which I thought was great. It was like, “Let’s just do the same thing we did on the first day of summer, but this time as a musical. What what assurances do we have that everybody else would join in and sing and know all the choreography? I don’t know. I guess they will. I think that will work.”

SWAMPY: My favorite Doofenshmirtz device is the Chicken Replacinator, which again, was the one that we came up with for a very specific reason, obviously, and we have now used it in three episodes. 

DAN: And a movie.

SWAMPY: We did not realize just how versatile it is to replace something with the nearest or farthest chicken. I want to build a functioning model of that. Wouldn’t that be great?

That would be great. The first episode of Season 5 marks the first day of a new summer vacation and Linda disappears. Where did this idea come from? 

DAN: We did a lot of talking in the early days in the new writer’s room about what would be the perfect episode back. And we decided that it should be an episode that feels like it’s going to end like every single episode. Not every single episode, but most episodes end with mom coming home and everything disappearing right before she sees it. And set that all up and then have some twist happened that makes it into a two-parter.

SWAMPY: Knowing our writer’s room, it probably started with somebody saying sarcastically, “Let’s just kill off a main character!”

DAN: Yeah, and we’re like, “OK, let’s try it. Let’s see what happens.”

SWAMPY: I have to say over the years, some of the best things we’ve ever done has started with one or the other of us saying something that we think is completely unusable just to make the other guy laugh and break the tension. And then the other one going, “Hmm, wait a minute.” 

DAN: Maybe, maybe. We’ve been answering this question for the last two years, where people say, “Is there anything you can tell us about the new season?” And I always say, “Well, in the first episode, we kill off a main character. And then later, the kids help their dad build a bookshelf.” And it gets a big laugh because it sounds like I’m lying. And both of those things were true. 

When Season 4 ended, Doofenshmirtz was no longer evil – but in the Season 5 premiere, we learn that he’s resorted to his old ways. 

DAN: He spends a lot of that school year in Milo Murphy’s Law, which is our other show. He appears in that for the whole second season. But he’s not very good at it yet.

SWAMPY: He does realize at a certain point that it’s not working for him. It’s still there in his future. 

DAN: [In Doofenshmirtz’s voice] I’m gonna try that whole evil thing again. I’m gonna give that one more try before I go completely good.

SWAMPY: My favorite reaction is his daughter coming in and going, “Oh, we’re doing the whole evil thing again. OK, great. Hi, Perry.”

Swampy, I saw a video of you singing with Michael Bublé, who is one of many guest stars this season. What was that experience like?

SWAMPY: I, um, that’s gonna get me. Sorry.

DAN: Swampy’s granddad wrote “Sentimental Journey.”

SWAMPY: I made a joke to him saying, “How come I haven’t heard you do ‘Sentimental Journey’?” And we just started singing it. He sang along and I got to sing my grandfather’s song with Michael Bublé. Yeah, it was just one of the coolest things ever. He’s one of the nicest guys. 

DAN: Michael’s just a big fan of the show and he reached out to me on TikTok as he’s big on TikTok too and and we ended up having lunch and talking about what we could do together. I said, “Look, if you want to come and sing a song on the show, we will write a song specifically for you to sing.” And he’s like, “I will absolutely do that.” And then a couple months later we wrote the song and sent it to him and he was like, “I am in!”

SWAMPY: The song is called “Tropey McTrope Face.”

DAN: He texted me and said, “You would have loved being a fly on the wall in the meeting with my manager, where I told him what I really wanted to do at this point in my career was sing a song called ‘Tropey McTrope Face.’” And I was like, “Well, I’m glad we got you then.”

SWAMPY: Yeah, but that little video of me singing with him, my mom saw it and she called me crying. Thank you, Michael.

DAN: We shot that a year ago, almost. It was sometime last year, maybe not a whole year ago, but it was a long time ago. And it’s just been on my phone waiting for it to be announced that Michael Bublé was in the show before I could post it and then I found it.

John Stamos, Anna Farris, Alan Cumming and Meghan Trainor are among some of the other cameos this season. Who were you both most excited about working with? And who would be your dream guest?

DAN: I mean, Meghan Trainor just knocked [it out of the park].  We wrote a song for her, and she just went off and did all these harmonies and stuff to it and it sounds fantastic. She’s also a character in the show. That was fantastic. I know who Swampy’s gonna say. He’s gonna to say Helen Mirren, because he’s been saying that for a long time.

SWAMPY: I always say Helen Mirren. If you want to do a cartoon, Helen, call us. But one of the fun things is we got to grab a couple of the folks from the Ted Lasso cast, which I am in love with every frame of Ted Lasso. I ended up becoming friends with Cristo Fernandez. And then he turned us on to Coach Beard, Brendan Hunt. And both of them said yes and came out and [we] just had the best day with them. So that was fun, too. 

A Ted Lasso and Phineas and Ferb crossover!

SWAMPY: Well, they occupy a very similar space of positivity in the world. And when I started watching it, I originally said to my wife, “This is kind of the live action, spiritually and emotionally, the live-action version of our show.” It’s really good-natured at its core. 

DAN: They get a lot of what feels like edgy humor out of characters being really nice and genuinely good people.

SWAMPY: And I think we need more of that in the world today.

I can’t let you go without bringing up the iconic musical numbers in Phineas and Ferb. I’ve had “Squirrels In My Pants” playing in my head for over a decade, now I think it’s going to be “License to Bust.” Do you each have a favorite song you’ve co-written? 

SWAMPY: We have a mutual favorite. I mean just as far as musically, and Dan talks about it the best, was “Summer Belongs to You.”

DAN: The writing process on that was fantastic because we didn’t have that title for the song or even for that – that’s what our first hour-long special was called. We knew what was gonna happen but we weren’t set on a title. When we [were] structuring all the chords to build up to a big, big chorus, we had not written the chorus yet and we got up to that point and then I just started singing, “Summer belongs to you,” and he and Martin started doing the answer backs. And we’d sang the entire chorus exactly the way it is. By the end of it, I was singing the last bit and they were singing along as we were writing it. It was this magical moment that never happens. We just all had goosebumps. And we jumped up and down in the room. That occupies a sweet spot.

SWAMPY: To me, the first things we wrote together, it was the theme song and “Gitchie Gitchie Goo” and Perry the Platypus theme. Those were the first ones, kind of the genesis, so those I absolutely love. 

What else can you tease about what’s to come in Phineas and Ferb Season 5? And the million-dollar question – will Phineas and Ferb top their last summer vacation?

DAN: We’re trying!

SWAMPY: Oh, I think they have. We’ve done some things that I think really are the best episodes we’ve ever done. 

DAN: Yeah. I think there’s like six or seven episodes this season alone that I think are going to supplant people’s favorite episodes of all time. It’s like, “Oh, ‘Dude, We’re Getting the Band Back Together,’ was my favorite episode, but now it’s this.” There’s so many that I’m just like, “I think this might be my favorite thing we’ve done.” What we hope is that people watching the fourth season on Disney+ could just go right into the fifth season [and] they wouldn’t notice it. The only thing we changed in the characters is we put an extra stripe on Phineas’s shirt because it’s a year later. 

SWAMPY: To give the illusion that he’s grown. He’s not any larger on the model sheet. Just has an extra stripe.

DAN: He’s exactly the same, he just has an older shirt.

That’s funny that you say that because I didn’t realize at first that it was a Season 5 and not a totally new show, but when I was watching it, it felt like the last 10 years didn’t even happen.

DAN: Excellent! That’s what we want.

I loved it. Reboots and revivals can be tough because you want the essence of what it was when you first watched it and I feel like this show does that.

SWAMPY: Yay!

DAN: Disney was very clear and said, “Look, we don’t think it’s broken, you don’t have to fix it. There’s not anything we want you to do that’s different. That being said, you have total autonomy to do with it what you will.” And we just said, “We just want to make more of this.” And they said, “We’re perfectly OK with that.”

This interview has been edited for length and clarity.

The first two episodes of Phineas and Ferb Season 5 will premiere on Thursday, June 5 at 8 p.m. ET/PT on Disney Channel and Disney XD. The first 10 episodes of the season will begin streaming on Disney+ on Friday, June 6.