Phineas and Ferb return this summer with zany new episodes and a small change

NEW YORK — The beloved cartoon duo Phineas and Ferb are returning for new episodes this summer after a decade away and pretty much nothing has changed. Except maybe one thing.

''The more observant of you will notice Phineas' shirt has one extra stripe,'' says co-creator Jeff ''Swampy'' Marsh. Dan Povenmire, Marsh's creative partner, adds: ''He hasn't actually gotten any taller, but we're giving him the illusion of getting taller.''

Other than a fourth stripe on Phineas's orange-and-white T-shirt, ''Phineas and Ferb'' returns with all the characters that Gen Z viewers so adored, including Perry the Platypus, the mad scientist Dr. Doofenshmirtz, the easily excitable older sister Candace and the bully Buford.

''We were a little worried at first, like are we going to get in the writer' room and just get a lot ‘No, did that.' ‘Did that.' ‘Did that,''' says Povenmire. ''But it hasn't been like that at all. It's been great, fresh, new stories with these characters that we're just thrilled with.''

‘It's like old times'

The series restarts with Phineas and Ferb enjoying summer vacation, Doofenshmirtz back to his evil ways — he updates his social media status to ''Evil Again'' — and Candace is once more on her everlasting quest to get her brothers in trouble.

''Isn't it great? It's like old times,'' says Doofenshmirtz.

The decision to restart the series was a no-brainer. According to Disney internal streaming data, the show has been streamed some 650 million hours on Disney+ globally to date. According to Nielsen, ''Phineas and Ferb'' is among the top 10 most-watched animated kids series on streaming platforms despite not offering new episodes in 10 years.

The show — which had four seasons between 2007 and 2015 — centers on the titular stepbrothers — the triangular- headed Phineas and the quiet Ferb — who stave off boredom by turning their backyard into things like ski resorts, surfing beaches or monster truck rallies.

Unbeknownst to the pair, Perry, their mute pet platypus, is a secret government agent code-named P who regularly dons a hat and trench coat to save the world from Doofenshmirtz, voiced by Povenmire.

The show is pitched to both kids and adults, mixing references to Nietzsche and Girl Scouts. Each episode also includes an original — often very catchy — song, written by Povenmire and Marsh. (''Squirrels In My Pants'' is a proven winner.)

''It's something that the whole family can enjoy together,'' says Marsh. ''We made a commitment never to cut anything just because somebody said it was too smart. We just believed kids are smarter than you think.''

The idiosyncratic show had a hard birth, created in 1993 but not airing until 2007. Povenmire and Marsh, both veterans of shows like ''The Simpsons'' and ''Family Guy,'' hit it off and stuck with their vision.

''Whenever anybody would ask us to pitch them something, we would always dust this off and say, ‘Well, here's the show we really want.' And most of the time people were just like, ‘I think it's too complicated,''' says Povenmire.

The creators insisted on using no double entendres, took out mean humor and refused to make the moms and dads idiots. Even the so-called villains — Candace and Doofenshmirtz — are good, deep down.

''If you're trying to get a laugh, shocking somebody or putting somebody down are the two easiest, cheapest laughs to get,'' says Povenmire. ''We'd made this decision to make it nicer than the shows that we had seen on the air at the time.''

The show has been a magnet for celebrity cameos and the upcoming season is no different, with Michael Bublé, John Stamos, ''Ted Lasso'' stars Brendan Hunt and Cristo Fernández, Alan Cumming, Leslie Jones, Anna Faris, Megan Rapinoe, Meghan Trainor and Ruth Negga all making guest spots.

Phineas and Ferb's penchant for building things like a submarine sandwich submarine or a vaporizer machine has over the years had an unintended effect — inspiring a generation of engineers.

When Povenmire visits colleges, engineering students routinely approach to say his TV show was the reason they are studying the field. ''So we're expecting a thank-you letter from all of the engineering schools around the world,'' jokes Marsh.

Marsh recalls the first time he realized that he and Povenmire had a hit on their hands. He was with his child at an outdoor skating rink in Santa Monica early in the show's run when a little girl came skating by, singing their song ''S'Winter,'' a mashup of summer and winter (One lyric goes: ''You can freeze while you get tan''),