While Phineas and Ferb create an Anti-Gravity Fun Launcher to reduce the laws of gravity, Monogram worries the boys are out to destroy the Tri-State Area and sends Carl to investigate undercover. Meanwhile, after struggling to come up with a new design for an inator, Dr. Doofenshmirtz comes across the blueprints for the Anti-Gravity Fun Launcher on the internet... and decides to use it for his own nefarious purposes.
Tropes:
- Anti-Gravity: The boys' invention in this episode is a chamber that grants anti-gravity powers to whoever enters it. The effects wear off in just 15 minutes.
- Bad "Bad Acting": Monogram, when pretending to be Carl's father.
- Bait-and-Switch: Phineas, possibly out of habit, asks where Perry is, but, as Candace points out, he was next to them the whole time.
- Carry the One: Phineas posts his blueprint on the Internet so that Baljeet could check the math. Baljeet tells him he "accidentally placed a cosine where [he] needed a quadratic differential".
- Continuity Nod: The episode features an updated version of Carl's theme song from "Swiss Family Phineas".
- Costume-Test Montage: The updated version of Carl's theme song is set to one of these.
- A Day in the Limelight: For Carl.
- Demoted to Extra: Candace only has a minor role in this episode.
- Improperly Paranoid: Carl makes several massive leaps in logic to justify his theory that Phineas and Ferb might be helping Doofenshmirtz...simply because Phineas posted his blueprints online and Doof decided to steal them.
- New Powers as the Plot Demands: Norm in this episode is shown to have gained new abilities not even Doofenshmirtz knows about, namely to extend his arms and transform himself into a truck. Lampshaded by Doofenshmirtz:Doofenshmirtz: I should really read your operation manual.
Norm: Yes, yes you should. - Parking Problems: Doofenshmirtz's version of the Anti-Gravity Fun Launcher is towed away because he parked it in a loading zone (despite it not being a motor vehicle).
- Pixellation: When Perry appears on a talk show to look for Agent G, his face is (poorly) pixellated to conceal his identity. When he leaves, the pixellation stays in place, prompting the host to yell "Hey, buddy, you forgot your pixellation!".
- Self-Disposing Villain: With Perry out of the picture, Doofenshmirtz somehow manages to thwart himself in this episode; he gets his copy of the boy's Anti-Gravity Fun Launcher chamber towed away because he parked it in the wrong spot, and then when he stumbles upon the original chamber, he steals it and escapes with Norm before being ticketed and having his contraption towed again, this time because he doesn't have the correct license to drive a robot.
- Shout-Out:
- The opening scene where an apple falls on the boys' heads is a nod to the popular but disputed story that Isaac Newton began formulating the theory of gravitation after watching an apple fall from a tree.
- Some of the costumes Carl tries on during the Costume-Test Montage include outfits for a cowboy, a Native American, a cop, a steel worker, a Navy sailor, and a biker outfit.
- Significant Anagram: According to Carl, the boys' "Anti-Gravity Fun Launcher" invention is actually a codename for "Evil Fanatic Hunt r Raygun" [sic]. Monogram points out the missing "e", but Carl theorizes that it was an attempt to mislead the agency.
- Sheep in Sheep's Clothing: In spite of Carl's theories, he realizes that the boys and their friends are only after a good time and they only built their device for that purpose.
- Snipe Hunt: In order to keep him away from Phineas and Ferb, Monogram sends Perry on a literal "Wild Goose Chase" to find a nonexistent missing goose agent, Gary the Gander (aka Agent G). This is later subverted when Perry brings Agent G home. As it turns out, Agent G has been taking an extended vacation and living on The Moon.
- Subliminal Seduction: According to Carl, when the phrase "Ferb, I know what we're gonna do today!" is played backwards and with the syllables in a random order, it becomes "Let's help Doofenshmirtz destroy the Tri-State Area!".
- Subverted Catchphrase: Since Perry the Platypus didn't thwart Doof in this episode, he was instead thwarted by the fact of not having a license to drive a robot with more than two axles. As he is being towed, he yells, "Curse you, motor vehicle code!"
- Thinks of Something Smart, Says Something Stupid: While trying to covertly investigate the titular brothers' invention of the day, when asked his name, Carl thinks to himself, "Say a cool name, like Nitro Dax or Steel," and then when actually introducing himself, just says "My name... is Carl."
