Agent Doof

From now on, I'm going to be a good guy! Candace's plans to watch over Phineas and Ferb backfire when Dr. Doofenshmirtz's "Babe-inator" turns her brothers into babies. After having an epiphany, Dr. Doofenshmirtz shows up at the OWCA to give up his evil ways. Agent P has no choice but to show Dr. Doofenshmirtz the ropes of the trade, but things quickly sour between the two after Dr. Doofenshmirtz accidentally exposes the identity of a fellow animal agent.

Episode Summary
Linda is heading to Vivian's aunt's sister's landlord's son's baby shower, and leaves Candace in charge, who tells Phineas and Ferb not to do anything while recording it.

Agent P heads to his lair and is surprised to see Dr. Doofenshmirtz on the screen. Major Monogram says that he has turned to the good side and written the "I give up" application and since he was raised by ocelots it supposedly makes him an animal, but tells Agent P he needs to supervise him. Doofenshmirtz explains that he quit evil after trying to use his "Babe-inator", which he plans to turn his brother and the people into babies, and failed; Making him think that he's not good at being evil, which made him decide to be good and Agent P gives him his own cubicle.

Later it was revealed that even though the Babe-inator wasn't plugged in, Norm plugs it back while cleaning up the lair. The Babe-inator activates and it then hits Phineas and Ferb, turning them into babies. Thinking that Phineas and Ferb caused this to happen, Candace tries to take a photo of the two, who have now been turned into babies, and sends it to Linda successfully. However, she simply thinks it is a baby photo of them. Candace then attempts to take a photo of them with a newspaper, but Phineas throws her phone in a fountain and Ferb tears apart the newspaper. She decides to use a stroller and take them to show her.

Doofenshmitz, meanwhile, is in his cubicle checking the computer and finds out that Newton the Gnu is Agent Silent G and he blogs it. He then goes on a coffee break with the other agents and ignores the screen that warns of a security breach and an agent captured.

Candace goes through the park and Phineas and Ferb start crying. They go to a store where Candace leaves them outside to get toys for them to quench their sadness while a robber arrives on his motorcycle and breaks into the store. The babies then use the motorcycle and hook it up to the stroller and escape, while Candace chases them and catches them while the robber is caught by the cops.

Doofenshmirtz and Agent P are called to Monogram's office to hear that someone revealed Newton the Gnu's secret identity, and has been caught by his nemesis, Dr. Diminutive. He ordered Doofenshmirtz and Agent P to head out to save him. They takes the hover-jet and Doofenshmirtz presses a button that fires a missile, which accidentally destroys Monogram's car.

Doofenshmirtz and Agent P make it to the apartment where the agent is being held where Doofenshmirtz attempts to kick down the door but gets his foot stuck. Dr. Diminutive appears, who has Agent Silent G captured and now he catches them too with his Photon 2000 particle bubble-"erator". Dr. Diminutive tells them that he quickly learned Newton the Gnu's identity when Doofenshmirtz put it in his blog. Candace chases the babies in a toy store and finally catches them.

Dr. Diminutive hangs them all off the edge of the apartment and drops them 40 stories down, but Agent P uses his grapple gun to catch the particle bubble-inator to trap Dr. Diminutive in a bubble and saves them by using it to create a bigger bubble, which they ride into and Doofenshmirtz taken them to safety and later crash into Monogram's office.

Candace arrives at the baby shower but the boys are taken by the Fireside Girls who are helping out at the event.

Back at the O.W.C.A, Monogram's office was being repaired and Monogram with an arm cast was forced to stay in a cubicle. Monogram congratulates Agent P for rescuing Agent Silent G and then fires Doofenshmirtz for numerous complaints in Human Resources.

Doofenshmirtz blames the duck agent and tells him he does so much damage for being good that tells him to returns to evil after believing he is better off that way. He then calls Norm to polish off his -Inators and leaves, which Norm starts off with the Babe-inator and it hits Linda and the Fireside Girls (except Holly and Adyson) thus turning them into babies while Candace is trying to explain to them that Phineas and Ferb have been turned into babies. She breaks the Fourth wall that she hopes it wears off before the next episode.

Songs

 * Here's Why It is Great to Be a Baby

I know what we're gonna do today!
None

Ferb's Line
''' He also cries along with baby Phineas.

Whatcha doin'?
None.

Oh, there you are, Perry
None.

Perry's entrance to his lair
He twists a board on the fence, turning it into a diving board. Then he dives into a baby pool, and the water floods into the lair, along with Perry.

Background Information

 * This episode reveals that the characters in Phineas and Ferb are aware that they are being filmed during each episode.

Production Information

 * This is the third-longest an episode (along with "Phineas and Ferb and the Temple of Juatchadoon") which has had its segments air separately.
 * When this episode premiered on Disney Channel in the USA, it was paired with "Minor Monogram", then later paired with its partner, "Phineas and Ferb and the Temple of Juatchadoon". For reasons unknown, it was later paired with "What A Croc!".
 * However, this episode was still paired with "Phineas and Ferb and the Temple of Juatchadoon" on Disney XD in the US.
 * This first aired on Disney XD on Demand Canada on March 26, 2012.
 * This first aired in Europe on Disney Channel Spain and Portugal on April 19, 2012.

International Premieres

 * March 26, 2012 (Disney XD Canada)
 * April 19, 2012 (Disney Channel Spain and Portugal)
 * May 10, 2012 (Disney Channel Latin America, On Demand)
 * May 21, 2012 (Disney XD UK)
 * June 16, 2012 (Channel 13 Chile and Unitel Bolivia)
 * July 7, 2012 (Disney XD Poland)
 * July 24, 2012 (Disney Channel Brazil)
 * August 13, 2012 (Disney Channel Latin America, Official Premiere)
 * September 14, 2012 (Family Channel)

Errors

 * Before Isabella was hit with the Babe-inator, she was wearing her Fireside outfit, but after she was hit, she switches to her regular pink outfit.
 * Some of the Fireside Girls have their sashes on their right shoulders instead of their left before and after getting affected by the Babe-inator.
 * During the end of the episode when all the agents were fixing the agency you can see that there are two pig agents. One is the regular one wearing a fedora and another one is seen wearing a hardhat. This could mean that the agency might employ more than one agent of the same species.
 * During one part of Great to Be a Baby, Phineas, Ferb, and Candace can be seen in their own house, despite being in the store before, for most of, and after the song. They also appear to be in Isabella's kitchen in one shot.
 * Linda should've gotten a little suspicious when she saw the picture of Phineas and Ferb as babies because they didn't meet each other until they were at least 5 years old as seen in "Phineas and Ferb Get Busted!" and Phineas and Ferb The Movie: Across the 2nd Dimension. (Maybe Linda thought it was a montage.)
 * The sign said "Danny The Dinosaur's Baby Stuff Emporium," but Danny looked like a dragon, not a dinosaur.
 * If Perry jumped through the hologram of Dr. Diminutive, Dr. Diminutive shouldn't have been able to open the door to them.
 * Candace was eating health squares but they were cylinders.
 * After Katie was affected by the Babe-inator, her party hat turns orange.
 * When Carl is washing Monogram's car a handicap spot marker can be seen on the ground  in the space above the car.  When Doofenshmirtz blows up the car the handicap space marker is gone.

Continuity

 * It was mentioned that Doofenshmirtz was raised by ocelots again. ("The Chronicles of Meap", Phineas and Ferb The Movie: Across the 2nd Dimension, "Skiddley Whiffers").

Allusions

 * The Hard Way - The partnership between Doof & Perry copied from relationships between Nick Lang & John Moss in the movie.
 * The Karate Kid - Monogram tells Carl washing his car will teach him karate, which is what Mr. Miyagi tells Daniel in this film.
 * Happy Hallow Park &amp; Zoo - Danny the Dinosaur is nearly identical to the San Jose children's park/zoo mascot.
 * Discover Card Commercial - The tune of the end of Great to Be a Baby is similar to the tune of the commercial.

Trivia

 * Dr. Diminutive has his own nemesis named Newton the Gnu a.k.a. Agent Silent G.
 * First time Isabella and the Fireside Girls (except Holly and Adyson) were seen as infants.
 * Candace breaks the fourth wall at the end.
 * Major Monogram's car is a black sedan.
 * Like Phineas, Dr. Doofenshmirtz also scratches his ear when lying/covering up a lie.
 * It is never explained what happened to Phineas, Ferb, Linda, Isabella, and the Fireside Girls (except Adyson and Holly) at the end of this episode. Maybe the Babe-inator zapped them again, and they were turned back into their normal selves.
 * Though the most plausible explanation is when Perry eventually returns home and sees what happened, since he knows what the Babe-inator is, he can easily go back to Doofenshmirtz and reverse it.
 * Fourth time the O.W.C.A. headquarters are seen. ("Traffic Cam Caper", Phineas and Ferb The Movie: Across the 2nd Dimension, "Delivery of Destiny")
 * Second time Ferb is shown crying, the first being Phineas and Ferb The Movie: Across the 2nd Dimension.
 * Fifth time Candace lost her cellphone. ("Greece Lightning", "Candace Disconnected", "Meatloaf Surprise", "Meapless in Seattle")
 * Agent M appears again. ("Phineas and Ferb Musical Cliptastic Countdown")
 * Fourth time Phineas is seen as a baby. ("Phineas and Ferb Get Busted!", "Oh, There You Are, Perry", "Phineas and Ferb Summer Belongs to You!")
 * Third time a character goes to a baby shower, second time it was Linda. ("Attack of the 50 Foot Sister", "Tour de Ferb")
 * Second time Doofenshmirtz "gets on the good side". ("Voyage to the Bottom of Buford")
 * Phineas and Ferb get hit with one of Doofenshmirtz's Inator's again. ("Gaming the System", "Canderemy", "Phineas and Ferb Interrupted")
 * Second time a character is told washing something will teach them karate. ("Doof Dynasty")
 * Second time someone got their foot stuck in a door. ("Chez Platypus")
 * Doofenshmirtz and Monogram interact again. ("Phineas and Ferb Musical Cliptastic Countdown", "Phineas and Ferb Summer Belongs to You!", "Candace Gets Busted", "Perry The Actorpus")
 * Second time Linda is seen as a baby. ("Mom's Birthday")
 * Many agents of the O.W.C.A. appeared. ("Cheer Up Candace", "Phineas and Ferb Christmas Vacation!", Phineas and Ferb The Movie: Across the 2nd Dimension)
 * Candace was eating "Health Squares" cereal at the start of the episode, the same kind of cereal Jeremy ate on his day to visit colleges. (Phineas and Ferb The Movie: Across the 2nd Dimension)
 * Doofenshmirtz leaves his Babe-Inator unplugged. This is the exact opposite of what he does to his Shrink-Inator. ("Does This Duckbill Make Me Look Fat?", "Let's Take a Quiz")
 * Fourth episode having the word "Doof" in its title, the others being "Hail Doofania!", "The Doof Side of the Moon" and "Doof Dynasty".
 * This episode reveals that Dr. Diminutive builds -erators, like Doofenshmirtz's -inators and Rodney's -inizers.
 * The joke that Doof tells during the coffee break is the classic "Duck walks into a bar" joke.
 * Phineas only has three lines in this episode before getting zapped by the Babe-inator.

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, Burglar
 * Dee Bradley Baker as Perry, Dr. Diminutive, OWCA Agents
 * Alyson Stoner as Isabella
 * Tyler Alexander Mann as Carl