In their one hundred and four days of summer vacation, the eponymous stepbrothers in Phineas and Ferb built a variety of high-concept contraptions and devices. If it's possible in cartoon logic—as almost anything is—the show probably did it. From 2007 to 2015, creators Dan Povenmire and Jeff "Swampy" Marsh set the boys on countless thrilling adventures.

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In real life, the secrets behind the making of the show are as interesting as what was on screen. Read on for ten things about Phineas and Ferb that you may not have already known.

Since animation, as an art form, relies on the actors' voices rather than their faces, it is a common occurrence that fans are surprised to learn that an actor they have seen before is also the voice of a familiar cartoon character. This is especially likely given some natural talents who are able to alter their speaking voice for a part. In this case, fans of 30 Rock may have been unaware that two regular cast members also starred on Phineas and Ferb.

Actor/comedian Jack McBrayer, who played Kenneth Ellen Parcell on 30 Rock, provided the voice of Irving, Phineas and Ferb's number one fan. Meanwhile, Maulik Pancholy, also known as Jonathan on 30 Rock, played the regular role of Baljeet Tjinder on Phineas and Ferb.

The Young Voice Cast Were Familiar Faces To The Audience

While many animated programs rely on seasoned voice actors to play kid parts, Phineas and Ferb had a degree of authenticity by having young actors playing characters only slightly younger than themselves. In addition, they were each well-established, with a familiar voice, but perhaps not a recognizable voice if that was the only component available.

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At the time of Phineas and Ferb's premiere, Vincent Martella (Phineas) was starring as Greg on Everybody Hates Chris. Thomas Brodie-Sangster (Ferb) was known for Love Actually and Nanny McPhee. Ashley Tisdale (Candace) and Mitchel Musso (Jeremy) were Disney Channel veterans, with the former appearing in The Suite Life Of Zack and Cody and High School Musical. Alyson Stoner (Isabella) had appeared in a variety of children's programming including Suite Life, Drake and Josh and That's So Raven, as well as the Cheaper By The Dozen film series.

Three Voice Actors Appeared On The Same Live-Action Series

Aside from playing Candace, one of Ashley Tisdale's best known Disney Channel roles was as candy counter girl Maddie Fitzpatrick on The Suite Life Of Zack and Cody. In that show's three-year run, a number of actors guest-starred, including two fellow future important Phineas and Ferb cast members.

Caroline Rhea, known for playing Linda (Mom) on Phineas and Ferb and Aunt Hilda on Sabrina The Teenage Witch appeared as Ilsa, a hotel inspector from Germany in multiple episodes. Also, Alyson Stoner guest-starred as the twins' friend Max in multiple episodes during the first two seasons.

The Creators Voiced Key Characters

Among the kids, teenagers and their families on Phineas and Ferb, there are two notable adult male characters;  inept evil scientist Dr. Heinz Doofenshmirtz and O.W.C.A leader Major Francis Monogram. Rarely in a scene together, they represent the two opposite sides of Agent P's life as a Secret Agent.

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As it turns out, the two men behind the voices are even more important in life: series co-creators Dan Povenmire and Jeff 'Swampy' Marsh. The former voices Doofenshmirtz while the latter lends his vocals to Major Monogram.

13 Years To Sell/15 Years To Make

While Phineas and Ferb did not hit Disney airwaves until 2007, the idea existed in the minds of Povenmire and Marsh for much longer. Conceiving the idea as a way to work together uninterrupted, their concept was frequently rejected due to its complex nature. Eventually, their persistence paid off.

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Over a decade after originally creating the series, Disney picked it up. On top of that, it took a further two years for the show to be ready for production. With the stories, drawings, cast, and music in place, the rest, as they say, is history.

Dan And Swampy Worked On Other Well-Known Shows

Of course, before and during Phineas and Ferb's unsuccessful development stage, the creators worked on many other acclaimed animated series. The pair first met on The Simpsons where their office space was located opposite one another before formally pairing up on Rocko's Modern Life

To make a living when Phineas and Ferb still hadn't been sold, they also worked individually on well-known cartoons. In particular, Povenmire became a storyboard artist and director on Family Guy where he remained for seven years. Meanwhile, Marsh relocated to the United Kingdom, working on various series including Postman Pat.

Ferb Had A Different Voice Actor

While he does not speak often, it is a well-known plot point that Ferb Fletcher, unlike his step-family, hails from the United Kingdom. When he does speak, he's voiced by Thomas Brodie-Sangster, also known as "the kid from Love Actually." In Milo Murphy's Law, David Errigo Jr. did the voice.

However, Ferb only became British as a result of Marsh's time in the United Kingdom where he had developed a fondness for the people. Originally, Ferb was American and to be voiced by Mitchel Musso. Musso, of course, ended up playing Jeremy Johnson instead, ironically having more lines despite not being a title character.

Perry Is "Voiced" By A Well-Known Vocal Artist

On the show, Perry the Platypus—or Agent P, as he's known to some—is more of a mammal of action than words. He can't speak because he's a platypus. Rather than words, Perry is instead known for his iconic sound, usually when found by Phineas and Ferb at the end of an episode.

You may find it surprising that this vocal effect is provided by an actual human being, rather than a machine. Dee Bradley Baker, who also plays Klaus in American Dad, many alien creatures in Ben 10, and the Clone Troopers on Star Wars: The Clone Wars, is the man behind Perry.

Vanessa's Voice Actress Has Multiple Connections To The Show

Vanessa Doofenshmirtz, Heinz's daughter, is voiced by Olivia Olson, who also plays Marceline on Adventure TimeIn addition, she had acted in live-action and is also a singer. However, she is intricately linked to Phineas and Ferb for very specific reasons.

While Dan Povenmire plays her father on the show, her actual father, Martin Olson, also works on Phineas and Ferb. He is a songwriter and composer who has written much of the music alongside the two creators. Furthermore, one of Olson's best-known roles is Joanna in Love Actually, where she played the love interest to Thomas Brodie-Sangster's Sam. This mirrors Phineas and Ferb where Sangster's character Ferb is romantically interested in Vanessa.

Rocky Horror Picture Show Plays A Big Role

Some of the Disney viewers may not be aware of Rocky Horror Picture Showcreated by and starring Richard O'Brien. It has been both a feature film and stage play, and it is most definitely not for kids. Yet, much of the main cast has appeared in Phineas and Ferb, an animated series.

Creator Richard O'Brien has a recurring role as Lawrence Fletcher, the boys' father. Tim Curry (Dr. Frank-N-Furter) plays various characters including Worthington Dubois and Dr. Lloyd Wexler. Barry Bostwick (Brad Majors) plays Clyde Flynn, maternal grandfather and father-in-law to O'Brien's Lawrence Fletcher.

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