Suddenly Suzy

Candace panics when she inadvertently agrees to babysit Jeremy's little sister Suzy but to her surprise, Suzy is docile in the absence of her brother, saying that when Jeremy isn't around, she's "off the clock." The two of them bond and Suzy shows Candace how to get Phineas and Ferb to bust themselves. Meanwhile, the boys build a replica of Niagara Falls in their backyard with the intention of riding over the falls in a barrel. Back at Doofenshmirtz Evil Inc., Dr. Doofenshmirtz decides to increase his carbon footprint, (though he doesn't know what that is), by inventing a Carbon Footprint-inator.

Episode Summary
Candace is talking to a paper mache version of Jeremy in her room when Jeremy actually calls her. He asks her to look after Suzy, since his parents aren't home and he got called into work. Candace, in a love-induced daze, agreed without really listening to him; she realizes her mistake only after he hangs up. Candace rushes to ask Linda for advice, but Linda only sees it as a babysitting job for Candace. Linda then proceeds to the store to get a replacement part for the sprinkler, comparing it to Niagara Falls in front of. Ferb tells Phineas that Niagara Falls is a huge attraction for daredevils, which gets Phineas thinking.

Candace, in preparation for Suzy's visit, removes anything even remotely dangerous from the house, and greets them wearing a large foam suit. Suzy asks Candace if she wants to have fun, and Candace fears the worst. Suzy, however, only humiliates Candace as a means to control her brother. Candace is amazed by this ability, and when Suzy learns that Candace cannot control her brothers, she considers this unacceptable and declares that they are going to the backyard!

Meanwhile, Major Monogram and Carl are unshaven as they warn Perry that Dr. Doofenshmirtz has NOT bought anything in bulk from the internet, which concerns them. Doofenshmirtz is interested in increasing his own carbon footprint; he doesn't know what that means, so he builds himself a large carbon foot made by carbon paper saved from the 70's. He traps Perry by tying him up in giant shoelaces.

Phineas and Ferb are busy making a replica Niagara Falls in their backyard, with the assistance of Buford, Baljeet and Isabella. Buford is chewing Tuff Gum, a super-strong gum chewed only by bullies. When Suzy comes out, she asks, "What'cha doin'?", to Isabella's annoyance. Using her usual sweetness, she has the boys give her a glass of lemonade. Candace is in awe of Suzy's skill, and after being coached by Suzy, tries to get the boys to bust themselves. She starts by imitating Suzy's method (wide-eyed and smiling widely), but it makes Phineas uncomfortable. She gives up and asks the boys to call their mother himself, which he thinks is a great idea. He borrows Candace's cell phone to call Linda, convincing her to come home.

The boys try out the waterfall ride, with Isabella and Baljeet in the barrel. Isabella tells Buford to leave his gum on the side as it is a choking hazard. Buford later jumps into the pool at the bottom, landing on Baljeet. Candace is excited at the prospect of the boys busting themselves. Everyone rushes out to greet Mom as she gets home.

Doofenshmirtz takes his carbon foot out via his dirigible. When Perry frees himself, he lunges at Doofenshmirtz, but he flies out a sliding window in the blimp. Instead, he follows by becoming a truck driver of a banana truck to the tune of Mobile Mammal. Doofenshmirtz first tries to stomp on the waterfall the boys built, but it sticks to the bottom of his foot thanks to Buford's gum. Complaining that nature always gets stuck to the bottom of feet, he shakes it off, causing it to crash into a spring water bottling plant. Doofenshmirtz's second attempt to destroy nature is foiled as Perry dumps his giant banana on top of his truck on the ground. The carbon foot slips on the peel, swings around and crashes through the top of his blimp.

Linda fixes the broken sprinkler in the backyard, which had been feeding the waterfall earlier, and offers Phineas and his friends some pie. Candace, upset at being foiled, blames Suzy, who responds lightly that "Results may vary." Jeremy returns to the backyard, prompting Suzy to once more embarrass Candace.

Songs

 * Tuff Gum
 * Mobile Mammal

End Credits
A repeat of Mobile Mammal

The "Too Young" Line
None.

Whatcha doin'?
By Isabella:

By Suzy:

By Candace:

Perry's entrance to his lair
Perry lays on the grass and it flips for a second to a bunny in a patch of snow, then it flips again and Perry appears in his lair.

Evil Jingles
Doofenshmirtz Evil Incorporated and Doofenshmirtz Carbon Footprint

Background Information

 * Currently listed on the Disney Channel TV Schedule.
 * The episode was aired first in Latin America (January 27th, 2010) on Disney Channel entitled "De Pronto, Suzy" (Suddenly Suzy).
 * Goof: When Phineas ask his friends about making a trial run on the Niagara Falls, Buford shorts turn black instead of brown.
 * Goof: When Buford puts his gum on the of the Niagara Falls hose he puts it on the side of it, but when Dr. Doofenshmirtz picks it up with his carbon foot it's on top of the hose.

Continuity

 * The mountain that was built by Phineas and Ferb resembles the mountain seen in "Isabella and the Temple of Sap".
 * The shop-owner and his wife from "Leave the Busting to Us" return. They also mention the golf course from "Put That Putter Away".
 * Once again Isabella expresses annoyance with others use of her catchphrase, First was ("Out of Toon").
 * Mr. Miggins makes a third appearance, ("I, Brobot" & "Boyfriend From 27,000 B.C.").
 * Goof: The shop owner's wife tells him that he "walk[ed] away from a profitable golf course", an obvious reference to "Put That Putter Away". However, the shop owner never had anything to do with the golf course. He didn't even appear in the episode; it was a separate character, a Scottish one.
 * Candace's shrine to Jeremy appears in the beginning ("Does This Duckbill Make Me Look Fat?").
 * Carl plays the Perry the Platypus theme on his one whisker.
 * Major Monogram's bobblehead outfit is the same worn by the dancers during "Lawn Gnome Beach Party of Terror".
 * The bunny in the snow patch is the same as the ones in "Leave the Busting to Us!".
 * Major Monogram appears to be trying to grow a beard. In "Phineas and Ferb's Quantum Boogaloo" he is seen in the future with a beard.
 * When Perry enters his lair the bunny resembles Dennis from the episode "No More Bunny Business".

Allusions

 * The title may be a parody of the song Suddenly Seymour from Little Shop of Horrors. A more direct allusion may be the 1990's sitcom Suddenly Susan, staring Brooke Shields.
 * Carbon paper is a type of paper (which, as Dr. Doofenshmirtz points out, is no longer used that much) which is placed in between two sheets of paper to create a copy of the original document as it is being written, from which the term "carbon copy" originates. Doofenshmirtz is taking literally the phrase "carbon footprint," which actually represents the amount of carbon dioxide emitted by a household or corporation. Reducing carbon footprints is a major part of the environmental movement popularized by Albert Gore and others in the late 2000s.
 * Niagara Falls is a large waterfall stationed between two towns sharing that name in New York and Ontario, Canada. Jumping Niagara Falls- especially in a barrel- is a popular stunt both in reality and fiction.
 * The mudflaps on Perry's truck mimic a popular mudflap design depicting the Warner Bros. character Yosemite Sam brandishing two guns with the inscription "Back Off!"
 * "Tuff Gum" may reference the popular sport's gum "Quech Gum."

Cast

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