Doofapus

The best way to defeat a platypus is to become a platypus!

Change is afoot when Candace accidentally liquefies herself by coming in contact with Phineas and Ferb’s device that turns solids into liquids. Meanwhile, Dr. Doofenshmirtz turns himself into a platypus to defeat Perry in battle, but finds it’s harder than he ever imagined.

Episode Summary
The episode opens with Phineas, Ferb, and their friends getting "Exotic and Unusual Smoothies". Buford then comments that the milkshakes are not as "exotic and unusual" as advertised. While Isabella thinks that they are exotic, that Phineas and Ferb could do better.

Perry enters his lair through a lengthy tricycle ride, and then Major Monogram tells him that Carl has stained the Agency's favorite couch. Carl defends himself by saying it was Agent M. Monogram then tells Perry what Doofenshmirtz has been up to. Doofenshmirtz was seen at the library checking out books on Eastern Australia and Hydrostatic Cell Fusion. He sends Perry off to find out why.

In their backyard, Phineas and Ferb present their latest invention, The State-of-the-Matter Transfer Device, which can turn any solid into a liquid, so they can enjoy all sorts of new and unusual flavors. Buford then tries it on a chicken. He then drinks the "liquid poultry", which he says, "tastes like chicken". Phineas then suggests "they try something more...". Ferb responds "Foul", which Phineas says "Yeah... No! Exotic."

Over at Doofenshirtz Evil incorporated, Perry is captured. He is then shocked to find out that Doofenshmirtz has turned himself into a platypus. Believing that turning himself into one would make them equally matched, he created the Platyp-inator, to turn himself into a platypus. To further level the playing field, Doofenshmirtz then traps himself in the same type of trap he had Perry in.

Candace then notices the device in the backyard, and goes to warn Linda. Since Linda is busy doing the laundry/stand-up routine, Candace goes to investigate and wait on her. Perry and Doofenshmirtz then begins to fight and the song A Platypus Fight is played.

She accidentally activates the machine, and gets turned to juice. A bird rolls over her, of which she does not approve. Phineas and Ferb then come back, apparently having gone to the store. Baljeet then steps on Candace. Phineas thinks that it is cool that Candace got turned into a liquid. She does not agree, but asks them to help her change back.

Meanwhile, Perry and Doofenshmirtz are worn out from even fighting each other and they take a break. They then have tea, to cool off. After it is over, the Platypus Fight resumes once more.

The first attempt to turn Candace back involves pouring her into a bucket and reversing the settings on the Device to turn her back into a solid. She is successfully turned back into a solid, but in the shape of the bucket she was in. They discover that she needs to be back into her original shape to return to her normal self. They use a life-size mold of Candace that Buford has to do the trick. Baljeet then inquires why Buford has a life-size mold of Candace, to which Buford replies that he has life-size mold of all his friends. Isabella says that she does not know how to feel about that. They pour Candace into the mold, and then they zap her with the machine. She walks out of the mold, looking like her original self. After coming out, she then goes to try and get them busted.

Doofenshmirtz, realizing that he can't win or lose as a platypus, he decides he needs something stronger. What he comes up with is "two platypuses". He then shows Perry his Double-inator. While explaining his advantage, Perry knocks Doofenshmirtz into the Double-inator, which sends out a stray beam. The beam then hits Phineas and Ferb's device, which creates a duplicate of it. They then zap each other, and turn into liquids, just before Candace can show Linda.

While Doofenshmirtz is distracted, Perry shoves the Platyp-inator into the Double-inator, defeating Doofenshmirtz. After what appears to be an explosion, Doofenshmirtz says that is good to be back to normal. He is then greeted by another Doofenshmirtz (presumably created by the Double-inator's explosion), who agrees with him. Doofenshmirtz then notices his duplicate, and is visually surprised.

Songs

 * My Undead Mummy (Instrumental Version)
 * Perry the Platypus (Second Verse of Extended Version)
 * A Platypus Fight

The "Too Young" Line
None.

Whatcha doin'?
None.

Perry's entrance to his lair
He rides a tricycle and enter to the underground parking lot and later an elevator to his lair.

Evil Jingle
Doofenshmirtz Evil Incorporated!

Background Information

 * Phineas reveals that he doesn't like zucchini.
 * Buford reveals he has life-sized molds of everyone.
 * This episode marks Stacy's birthday.
 * Isabella reveals that Buford has poor penmanship.
 * It is revealed that Perry owns a tricycle.

Production Information

 * This episode was aired on Disney Channel on Demand on June 29, 2012.

Errors

 * Since Phineas and Ferb's invention was reversed to make Candace solid again, the duplicate should have been made the same way, and therefore, neither of them should have melted. This is unless the device still had the melting ability or that Phineas and Ferb changed it back.
 * At the tea set with Perry and Doofensmirthz, the chairs are blue and then turn green.

Continuity

 * Fifth time the word "Doof" is in the episode name. ("Hail Doofania!", "The Doof Side of the Moon", "Doof Dynasty", "Agent Doof").
 * Seventh time a title of an episode has only one word. ("Rollercoaster", "S'Winter", "Atlantis", "Canderemy", "Bullseye!", "Excaliferb")
 * Second time someone else other than Perry is a platypus. ("Does This Duckbill Make Me Look Fat?")
 * Third time Doofenshmirtz has a platypus-related scheme. ("Greece Lightning", "Cheer Up Candace")
 * Third time Doofenshmirtz turns into an animal. ("Phineas and Ferb Hawaiian Vacation", "That's the Spirit")
 * Third time Perry fights with another platypus. ("Cheer Up Candace","Phineas and Ferb The Movie: Across the 2nd Dimension")
 * Second time Doofenshmirtz is seen with a platypus tail. ("Sleepwalk Surprise")
 * Doofenshmirtz decides to fight "fire with fire" again. ("Cheer Up Candace")
 * The title sounds like "Doof 'n' Puss". ("Nerds of a Feather").
 * If the above fact of Stacy's birthday being celebrated is true, then this would be the seventh character to have a birthday celebrated ("Candace Loses Her Head", "Raging Bully", "Mom's Birthday", "Dude, We're Getting the Band Back Together", "Run, Candace, Run", "Phineas' Birthday Clip-o-Rama!").
 * However, this is the first time the character celebrating their birthday isn't shown.
 * Third time Doofenshmirtz makes a duplicate of himself. ("Run Away Runway", "Mom's in the House")
 * Third time Candace accidentally hits herself with Phineas and Ferb's invention. ("Split Personality", "Let's Bounce")
 * Third time Perry has tea, and the second time it's with Doofenshmirtz. ("Day of the Living Gelatin", "Elementary My Dear Stacy")
 * Second time someone builds a device that turns things into liquids. ("Delivery of Destiny")

Allusions

 * FCC Regulations - The "Platypus Fight" has the line "If you're watching at home there's a seven second delay". This is a reference to the Television Delay rule set up by the FCC ever since the Super Bowl XXXVIII halftime show controversy.

Cast

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