Fan Theories About 'Phineas And Ferb' That Actually Make A Lot Of Sense

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Vote up your favorite fan theories.

Since its debut, the antics of Phineas and Ferb have caught the imagination of millions of viewers. And since its debut, fans of the show have offered their own hot takes and opinions regarding the storyline and characters. Here are a few interesting fan theories that have been shared by viewers. Vote up your favorite hot takes regarding the adored dynamic duo. 


  • 1
    527 VOTES

    Why Perry Lives With Phineas And Ferb

    From Redditor u/NS468:

    So Perry's mission is usually to stop Dr. Doofenshrmitz, but that may not be his only mission...

    His secondary mission may be monitoring Phineas and Ferb as potential threats.

    Why are they threats? Because they can create whatever they want, even destroy the earth if they feel like it.

    As seen in the movie, he does scan Phineas and Ferb's inventions Also, when Phineas say his iconic line "Ferb, I know what were gonna do today," Perry always leaves, because with the context of that line Perry knows that they are going to do something harmless for the day. In the episode in which Perry dreams that they found out his secret identity, a SWAT team comes and takes Phineas and Ferb, probably to lock them up in an effort to prevent them from becoming a threat.

    This "second mission" goes to other people's pets like Isabella's chihuahua .Isabella is a potential threat because she's shown many times to be highly skilled in combat, and she's the leader of the Fireside Girls, which are very militaristic, skilled, and organized.

    This "second mission" is to decrease the existince of people like Doofenshmirtz, who are incredibly gifted but use their gifts for evil, or when the "threats" are old enough they can recruit them.

    527 votes
  • 2
    428 VOTES

    Why Doofenshmirtz Is Enemy #1

    From Redditor u/yay855:

    Heinz Doofensmirtz is, simply put, not very evil. He's actually kind to children, a loving father, and just generally nice. However, he still has aspirations of conquering, albeit somewhat less grand than your average villain (the Tri-State area is not quite the size of the world), and his inventions are just as often useless as they are horrifying. He also has a tragic backstory that would make anyone else a sociopath at best, and his brother, though a very popular politician, is actually more evil than he is, as shown by the city-wide apathy towards giving children dangerous supplies and materials.

    Doctor Doofenshmirtz's first scheme shown was to cover the entire eastern seaboard in tinfoil. How would he accomplish this, you ask? Through a giant magnet. He had created a magnet powerful enough to cover the eastern seaboard in tin foil from a great distance away and targeted enough that it didn't effect every other piece of metal in the world. He could probably rip out the earth's core using that.

    His second scheme involved destroying all the lawn gnomes in the tri-state area using his destruct-inator, a machine capable of destroying anything instantly. A normal supervillain would use it to wreak havoc and conquer the world, but he just used it to destroy something that reminded him of his painful childhood.

    His third scheme was to take over the tri-state area using a skyscraper-sized robot. He would have succeeded, too, if Perry hadn't somehow gotten it to sneeze them out.

    As you by now can tell, Doofensmirtz is a very competent scientist - his first creation was a laser turret, and that was at a rather young age. The reason OWCA assigned their top agent to Doofenshmirtz instead of another villain is because Doof is highly dangerous but a terrible villain; Perry the Platapus is just the right mix of competent, confident, and kind that he will stop Doof if need be but also spend an hour sharing a meal with him. Perry knows that Doof is really a kind and brilliant man born to horrible people that didn't appreciate him in a country that didn't appreciate him, and he just needs someone to stop him from making a huge mistake and be there for him.

    TL;DR: Doof may be incompetent and a terrible villain, but his inventions are terrifying and he has more than enough tragic backstory for five villains. OWCA realizes the potential danger he is and sends their best agent to combat him, the two eventually becoming frenemies.

    428 votes
  • 3
    296 VOTES

    How Phineas And Ferb Can Afford To Build Their Inventions

    From Redditor u/Mutant_Llama1:

    In Phineas and Ferb, it's a well-known feature of the show that the things Phineas and Ferb create are insane for a kid to make. In real life, the things they make would require a lot of technical know-how, and in some cases outright breaking the laws of physics. However, let's keep some suspension of disbelief. Maybe these kids know things that the leading scientists of today don't. The real question is: how do they get the money for it?

    Roller coasters, rockets, and time machine parts costs money, don't they? NASA struggles to stay competitive in space with millions to billions of dollars, and although Phineas and Ferb are often shown dealing with contracts and legal paperwork, we never see money exchange hands. Who is paying for their builds?

    Let me propose this: I think that the OWCA knew that if Phineas and Ferb got too bored over the summer, they'd want to play with their pet, Perry. If they're playing with Perry, Perry can't be out stopping Doofensmirtz. Therefore, the OWCA spends millions of dollars allowing Phineas and Ferb to get unlimited amounts of materials for the cost of a kid's allowance, preventing them from ever paying attention to Perry except for the two lines in each episode where Phineas acknowledges Perry's existence briefly in-between planning his big moon mission or giant robot fight. This may explain why the OWCA always has budget cuts, despite being a federally-funded agency: because they're spending way too much on helping Phineas and Ferb break the laws of physics. On another hand, the OWCA could very well use Phineas and Ferb's research to create new gadgets for its agency,

    296 votes
  • 4
    488 VOTES

    Doofenshmirtz Is Phineas's Real Dead

    From a Redditor:

    So a few years ago, a fan theory emerged that Phineas (of Phineas and Ferb) is Doofenshmirtz's biological son. The main evidence for this was that Phineas' head shape looks a lot like Doof's, Phineas has a bit of the mad inventor about him -- he's always the one who chooses some crazy build as the thing he and Ferb are going to do today -- and that Linda and Doof dated when they were young, before Linda became a one-hit wonder pop star.

    This gained some traction before people pointed out the one very big hole in it: Candace. Not only does she not look anything like Doofenshmirtz, but she meets him in one episode and doesn't recognize him at all. Surely he couldn't be her father, so therefore he couldn't be Phineas's either, right?

    Well... not quite. Also consider that Linda is divorced. I think you can see where this is going.

    Here's my timeline. Let's assume for the sake of argument that the show is set in 2007, when the first episode aired. It's still early enough for smartphones to be a rare novelty, as indicated by Candace having a flip phone even though her family seems comfortably middle-class, but late enough for Candace to discuss an outdated marketing trend as being "so 2002" in the "Phinedroids and Ferbots" episode.

    * 1970s: Linda and Doof date for a while, as we see in that one episode that has them sitting in a car at a drive-in movie. However, Phineas cannot be a child from this relationship because 1) Candace and 2) Phineas would be in his twenties at least. However, this is still significant.

    * 1984: "You loved her in the '80s!" Linda somehow gets world-famous for that stupid, stupid song. She lives the pop star life for a while but then decides to settle down. Meanwhile, Doof goes to college (he may not be an actual Doctor, but he has to have some training to be able to build those inators without ordering the parts in a kit like Phineas does with the rollercoaster).

    * 1990: Linda gets married to Candace's father. Doof and Charlene are married by this time too.

    * 1991: Candace is born (assuming she's 16 in the monster truck episode). Vanessa is born a bit later.

    * After that, Linda's relationship with her husband goes downhill. Maybe he was just a former fan who loved her for her stardom rather than her personality, we don't know. Things grow distant. Linda is no longer satisfied with their relationship. One day, while she's out on the town, she runs into Doof, who has really improved himself since their awkward teenage days. Memories come flooding back. They resume their friendship. He becomes her shoulder to cry on. One thing leads to another.

    * 1995: Phineas is born.

    * Linda's husband starts to notice that "his" son looks nothing like him, finds out what happened, and divorces Linda. Doof and Charlene have no idea Doof has a secret kid.

    * After surviving on her own for a while, Linda finds it pretty darn hard living as a single mom with two kids, so she starts looking for another husband. She meets Lawrence, an engineer who's also single parenting.

    * 1998: Linda and Lawrence get married, introducing Ferb. Now we have the family we see in the show.

    488 votes
  • 5
    226 VOTES

    Dr. Doofenshmirtz Is Running An Insurance Scam

    From Redditor u/EquivalentInflation:

    In every single Phineas and Ferb episode, Perry foils Doofenshmirtz's plans, and destroys his inator, usually also damaging his tower in the process. Something like that should be catastrophic for Doof... but 24 to 48 hours later, he's got a brand new machine set up. It's mentioned that his wife gives him alimony, sure, but that's nowhere near enough to cover his rent, food, and high-tech machines, and she cuts him off partway through the show.

    Doofenshmirtz knows Perry will destroy his inators, which is why he took out a massive insurance policy on them.

    Remember, it's Doofenshmirtz Evil Incorporated. Doof is running a business, allowing him access to insurance. Major Monogram even mentions that OWCA has an insurance plan for their hoverjets at one point, so we know that there's some kind of insurance plan available for secret organizations and mad scientists (or pharmacists in this case). Doof then insures all his machines (likely overestimating their value, since he can claim they'd guarantee him the Tri-state area), and uses the money to fund his lifestyle, as well as building a new inator.

    That's also why Doof always gives such long monologues: he's filming the whole thing, and needs proof that he's making a legitimate effort. From his talks with LOVEMUFFIN, we know that the villainous speech is considered standard practice. He makes a video of himself trapping Perry, explaining his plan, and talking up his inator, then trying (and failing) to stop it from being destroyed. He can then use that video as evidence for his insurance claim. That's also why he gets so angry when Perry is reassigned to fight the Regurgitator, and why he sabotaged him: if Perry isn't there to fight Doof, he can't run his insurance scheme without revealing his fraud.

    One of the biggest pieces of evidence for this comes from the Across the 2nd Dimension movie: When Phineas and Ferb take apart Doofenshmirtz's inator, they note that the self destruct button is entirely unnecessary, and was actually stopping the machine from working. Why would Doof insist on adding a button to almost every one of his machines that allowed them to be easily destroyed? Because he wants to make it easier on Perry.

    Obviously, the seeming argument against this is that many of Doof's plans do work, and in a few cases, he even manages to succeed, like when he moves the Earth further from the sun, or becomes governor of the Tri-state area. But when you look at it more closely, none of that is surprising. Of course Doof's plans have to have a chance of success, otherwise, the insurance company would easily catch his fraud. He builds fully functioning machines, sets up an elaborate plan, and then attempts to put it into action. Remember, in the few cases he succeeded, it was sheer luck that Perry didn't beat him. If Doof gets lucky and wins, good, he's happy. If not, he gets a major insurance payout. Win win!

    The other argument against it would be that Doof asks his ex-wife for fiscal help in paying off his mortgage. However, there's an easy solution for that as well: Doof is a notorious cheapskate, as well as the fact that he doesn't want to draw attention to how much money he has. Somehow, he's managed to figure out a way to fly under the radar, but if he starts making big cash payments, he'll start getting a lot of questions... especially from the IRS. Like the Joker, Doof isn't crazy enough to mess with them.

    Finally, there's an obvious question: Doesn't this undermine Doof's whole relationship with Perry? Not at all, in fact, it actually strengthens it. By this point, Doof likely has enough money saved up to live comfortably. Instead, he chooses to keep making inators, because he legitimately wants to see Perry, and enjoys spending time with him. He also gives Perry a relatively easy job, keeping him safe. Other villains like the Regurgitator might actually just kill Perry once he's captured, and Doof wants to prevent that.

    TL;DR: Doofenshmirtz insures all of his inators for large amounts of money, then allows Perry to destroy them. However, he has to keep up the appearance of being evil, so all the machines still have to function and have a chance of success.

    226 votes
  • 6
    266 VOTES

    Why Phineas And Ferb Are So Smart

    From Redditor u/Hettus:

    It's uncanny how often Doofenshmirtz's inators hit something in Phineas and Ferb's backyard.

    So here's the theory: When they were younger, Phineas and Ferb were hit with one of Doofenshmirtz's inators while playing in the backyard. The inator significantly increased Phineas and Ferb's intelligence, making them capable of inventing and building the types of things that they do.

    266 votes