Ask a Foolish Question

Y'know, Mom's always doing nice things for us, I think it's time we did something nice for Mom!

When Candace discovers that Phineas and Ferb have invented a computer that can answer anything, she asks it how she can finally bust her brothers once and for all. Meanwhile, Dr. Doofenshmirtz loses the key to his latest invention, the "All Purpose-inator," and Agent P must find it before he does.

Episode Summary
Phineas and Ferb are thinking of what will they give to their mom for all the nice things she has done for them. As a result, they build a supercomputer so they can ask what they can get for her. Then, while the computer is being made, the song "Building a Supercomputer" plays, and, when they were finish building it, the supercomputer makes an initial scan of the whole Tri-State Area. They then tested it by asking simple questions, and it got all of their questions correct. Finally, they asked what they should get for Linda. The supercomputer said that they would have to get a gallon of industrial marking dye and a leaf blower, tie balloons onto them, and then go to the top of Danville Hill and release them exactly at 2:37 p.m. Meanwhile, Major Monogram reports to Agent P about some holes appearing throughout the Tri-State Area, and he suspects that Doofenshmirtz has something to do with it. As soon as Agent P got to Doofenshmirtz's lair, he got trapped in dry cement. Later he introduced the Metal-un-Earth-inator. Doofenshmirtz built it because when he was putting final touches on his All Purpose-inator, a device that can do anything, he slipped on green paint and dropped the key that activates the All Pupose-inator on the ground, and a gopher then took it away. As a result, he built the Metal-un-Earth-inator to attract any metal object. Back at the Flynn-Fletcher household, Candace asked the supercomputer how she can make Mom see what Phineas and Ferb have done. The supercomputer said that she has to build a device so her mother can see it. The kids concurrently released the balloons on top of Danville Hill, and then they followed them as they went home. Candace successfully built the device that was to reveal Phineas and Ferb's actions and, coincidentally, Linda comes home upset because of her awful hair just as Candance had finished her project. Candace brought her to the backyard as Doofenshmirtz's Metal-un-Earth-inator attracted the supercomputer. The balloons carring arrive overhead and pop over Linda's head. Linda's hair looked better when the hair dye fell on it and the leaf blower dried it, which made her happy. Thus the boys' plan had been successful.

Doofenshmirtz's lair ends up exploded because of the supercomputer.

Songs

 * Buildin' a Supercomputer

Perry's entrance to his lair
He pulls one of the flowers in the bushes and reveals a secret passage to his lair.

Background Information

 * http://www.toonzone.net/forums/showthread.php?t=281143
 * Baljeet seemed to be annoyed when viewing a computer screen showing Isabella thinking about Phineas. This further shows that Baljeet may have a crush on her.
 * Candace asks where Perry is instead of Phineas.
 * First time where the names of all the Fireside Girls that currently have names are mentioned on-screen.
 * The computer, from the time it was built, must have known the entire plot of the episode.
 * First time that the Fireside Girls were mentioned and most of their names revealed. When the Super-Computer answered Isabella's question, it mentioned each of their names in order from their first speaking cameo in the series:
 * Gretchen in "The Fast and the Phineas"
 * Adyson Sweetwater in "Tree to Get Ready"
 * Holly in "Raging Bully"
 * Katie in "Out to Launch"
 * Milly and Ginger in "Interview With a Platypus"

Errors

 * Along with "Misperceived Monotreme", most multiple line closed captions have to be read from bottom to top instead of top to bottom.
 * In the scene at Doofenshmirtz Evil Inc. after Candace starts to write down the list of items needed to build a contraptions to bust the boys, the helmets being attracted to the Metal-UnearthInator are all the same design.
 * When Linda returned home, she had bags under her eyes, but after her hair became it's normal but shiny in color, the bags are gone.
 * The second time Phineas gasps, his mouth doesn't move.
 * When Buford dances his tooth switches from left to right for a couple of times.
 * Perry Battles Doofenshmirtz with a Mace even though he Lost it when Doofenshmirtz Threw it off the Building.

Continuity

 * Isabella sees to be the same height as Phineas, but in all the episodes she always have been taller.
 * It is shown again that Baljeet may have a crush on Isabella. ("What Do It Do?").
 * The Jeopardy! theme is heard again. ("Fireside Girl Jamboree").
 * The Danville scrapyard is seen again. Also, the people in the yard mention that it's the "Second best scrapyard raid ever", referencing what Vanessa said. ("Brain Drain").
 * The supercomputer's voice is similar to that of Doofenshmirtz's Alien-inator ("Ladies and Gentlemen, Meet Max Modem!").
 * Phineas's head is seen with hearts around it again ("Run Away Runway"), only this time, it is his actual head instead of fabric cut-outs.
 * The green paint Doofenshmirtz slipped on may be the one he used in the previous episode.
 * The diving helmet appears again. ("The Lake Nose Monster")
 * A Roman helmet appears again along with a Roman Shield appearing again. ("Greece Lightning")

Allusions

 * The title refers to a common phrase/adage "Ask a foolish (or stupid) question, get a foolish answer."
 * The music that plays while Phineas and Ferb wonder what to do for their mom parodies the theme from the game show Jeopardy!
 * When Linda comes home her hair resembles Didi's hair from Rugrats.

Cast

 * Vincent Martella as Phineas
 * Ashley Tisdale as Candace
 * Thomas Sangster as Ferb
 * Caroline Rhea as Mom
 * Dan Povenmire as Dr. Doofenshmirtz
 * Jeff "Swampy" Marsh as Major Monogram
 * Dee Bradley Baker as Perry
 * Alyson Stoner as Isabella
 * Maulik Pancholy as Baljeet
 * Bobby Gaylor as Buford
 * John Viener as Norm