Phineas and Ferb build a super computer so that they can find the perfect way to do something nice for their mom.
In the meantime, Dr. Doofenshmirtz searches for the key to his All-Purpose-inator, an invention that he believes to be extremely evil despite not knowing what it does.
Tropes present:
- Ask a Stupid Question...: This moment. Also the title of the episode.Phineas: What's 2+2?
Super-Computer: 4. Try counting on your fingers. - Bad Hair Day: Linda had a coupon for a salon, but she was not satisfied with the result, which made her have a blonde perm. Fortunately, Phineas and Ferb's invention, and Candace's as well, turns her hair back to normal. It is not explained how she got her hairband back, though.
- Borrowed Catchphrase:
- After Candace refuses a homemade granola bar, she mutters to herself that she might give hers to Perry.Candace: Hey! Where is Perry?
- At the end, after Doofenshmirtz Evil Inc. explodes again, Doof uses the supercomputer's "Yeah, I knew that was gonna happen" catchphrase.
- After Candace refuses a homemade granola bar, she mutters to herself that she might give hers to Perry.
- The Cameo: Norm makes a brief appearance while the supercomputer scans all of Danville.Norm: Get out of my mind!
- Catchphrase Interruptus: Doofenshmirtz gets close to finish saying "Curse you, Perry the—", only for the roof of the Doofenshmirtz Evil Inc. building to crash back down just before he could say "platypus".
- Captain Obvious: The super computer. It may have cryptic meanings, but the ending had it be this way.
- Continuity Nod: "Between that and the random laser drills, this is like the second-best midday scrapyard rave ever!"
- Exact Words: Candace tries to exploit the Super Computer to bust Phineas and Ferb but she phrases her question vaguely. Candace hangs an indirect lampshade on this by realizing what happened at the end of the episode.Ferb: And by the way, nice use of the accordion arm.
- Just Eat Gilligan: Candace using the computer to bust her brothers would've been easier if she had asked it how to bust her brothers rather than "getting her mom to see what they had done".
- Lampshade Hanging: The lyrics of the "Building a Supercomputer" song is entirely comprised of this.We're building a supercomputer
And singing about what we're doing - Letting the Air out of the Band: When Doofenshmirtz attempts to grab some armor and a weapon from the pile but accidentally grabs a radio, a fan, and a handheld mirror.
- Made of Explodium: The super computer explodes upon hitting the Doofenshmirtz Evil Inc. building. This causes the roof of the building to explode shortly after. Twice.Doofenshmirtz: Why does everything explode so easily?
- Nap-Inducing Speak: Perry manages to play a game of solitaire while Doof is monologuing.Doofenshmirtz: You know, you can put the red king on the— Hey! You're not even listening!
- Noodle Incident: With the Tri-State Area itself. With all the gladiator helmets Doofenshmirtz unearths, you'd expect that there was some sort of war fought there before.
- Running Gag: Baljeet angrily insisting Phineas and Ferb give their mother a slide ruler.
