What Do It Do?

''Note: This episode premiered in the UK on October 24, 2009. Information is being added from this broadcast and contains spoilers for viewers in the US and other countries.''

Episode Summary
Lawrence is outside putting up a a bird feeder and house on a tree. He presses a button and the house opens. He decides that it doesn't do what he wanted it to do but leaves it. In the living room, Phineas and Ferb are watching a program on reverse engineering. It talks about what it is and how to do it. Phineas asks where Perry is once the program has finished and the scene cuts to Major Monogram asking Carl where Perry is. Carl says he came in early. Monogram then decides since Perry has his mission to go home.

Perry is already on Heinz Doofenshmirtz's hover jet and they are both fighting. Perry gets caught in one of the many traps that were set. Doofenshmirtz then tells him about one of his first dates. It was with Linda Flynn and they were in a car park, going to watch a film. Linda says that she would like to be a pop star one day and suggests to Doofenshmirtz that he should try to take over the Tri-State Area. Doofenshmirtz says it's unlikely but he'll try. He then brings out a machine to make the movie's sound 5th Dimentional and attaches it to their car. Unfortunately, the machine makes the cinema screen explode and blast off into the sky. Whilst finishing his flashback, Doofenshmirtz trips on one of his traps and knocks his latest machine into the Flynn-Fletcher House in the front lawn. Candace sees the machine and assumes that Phineas and Ferb built it. She calls Linda to see it and says the boys made it. Linda calls the boys and asks what that machine is. Phineas says they didn't build it but they wanted to know what it did. Linda says not to touch the machine so Phineas and Ferb do some reverse engineering and create a duplicate. Linda phones Lawrence whilst he is in the middle of a presentation about the history of Wistershire and Chedderton. She asks what that thing was in the garden and Lawrence says that he made it, thinking it was the bird feeder. He says he has to go and cuts Linda off.

Doofenshmirtz is still in one of his traps and presses a button to release Perry. Perry then tries to steer the jet away from Mt Kilimanjaro. The side of the jet hits the mountain and Perry falls into another trap. Doofenshmirtz then comments that his ship has as many traps as a golf course.

In the backyard, Phineas, Ferb, Buford, Baljeet, Irving and Isabella are trying to work out what it does. In the end, Baljeet and Isabella are having a "romantic" dinner when the machine picks up the candle and is about to destroy it. Phineas tells it to put the candle down and it follows his instructions. Everyone decides that it is an anti-romantic machine. Linda is still out the front of the house and she phones Lawrence again about the machine. Candace is meanwhile trying to get Linda to see what Phineas and Ferb had built. Candace explains that how Linda feels at the moment is how she feels when trying to bust the boys. Candace then says that she used the drag Linda to the machine. Linda decides to do the same with Lawrence and drags him out of his presentation. Whilst being dragged off, he asks if anyone has any questions. Everyone puts their hand up but Lawrence is out of the room before he can answer them.

Perry escapes his trap once again put grabs the scepter from the Earl of Whisteshire. He activates all of the traps and steers the hover jet again. Perry throws the scepter out of the jet and it hits the machine in the front yard. Candace is outside talking to Stacy about how she will bust the boys but the machine floats up, covers the mark it made in the grass and flies to the back of the house. It sees the duplicate and they both fall in love. They fly off into the sky just as Linda and Lawrence are getting out of the car. Candace is still trying to show Linda Phineas and Ferb's machine but then she sees them flying off into the sky. She gives up and walks away. Ferb is telling everyone about if you reverse engineer a heart you get lots of mushy red stuff. The episode ends in that scene.

Songs
What Do It Do? (song)

Whatcha doin'?
None

Perry's entrance to his lair
None.

Evil Jingle
Doofenshmirtz Rocket Power Jet Skiff!

Background Information

 * Currently listed on the following sites: MSN TV and the Disney Channel TV schedule
 * This episode has Linda mirroring Candace's behavior, trying to convince Lawrence of the strange gizmo as Candace tries to convince Linda of the boys' creations.
 * Baljeet is shown to show some affection to Isabella
 * Dr. Doofenshmirtz drove an AMC Gremlin to the drive-in movie theater.

Continuity

 * Phineas and Ferb do the same dance during the song as they did in Mix and Mingle Machine and Mother Nature Won.
 * The episode shows Doofenshmirtz date with Linda and she was the one who convinced him to try to takeover the Tri-State Area, which was mentioned in the 2009 Radio Disney premiere.
 * Irving reappears in this episode.

Allusions

 * Feeding Frenzy - Candace dance and sings (It's a Busting Feeding Frenzy; Stay outta water!) that about the game
 * Julius Caesar (the play by William Shakespeare)- Phineas addresses Isabella, Buford, Baljet, and Irving as "Friends, Bullies, Irving" similar to "Friends, Romans, Countrymen" from Mark Antony's speech.
 * Lawrence's tale about Whiskershire mirrors the story of The Pied Piper of Hamelin.
 * X-men: the stamp that the robot resembles the x-men logo.

Cast

 * Vincent Martella as Phineas
 * Ashley Tisdale as Candace
 * Thomas Sangster as Ferb
 * Alyson Stoner as Isabella
 * Caroline Rhea as Mom
 * Dan Povenmire as Dr. Doofenshmirtz
 * Jeff "Swampy" Marsh as Major Monogram
 * Richard O'Brien as Dad
 * Dee Bradley Baker as Perry
 * Jack McBrayer as Irving
 * Maulik Pancholy as Baljeet
 * Bobby Gaylor as Buford
 * Tyler Mann as Carl