On the inevitable 104th day of vacation, the season is coming to a close and it's Candace's last chance to bust her brothers; who build huge playground equipment for the finale of summer. She is quickly foiled, but when...
In "Day of the Living Gelatin", the boys make a gelatin dessert, but, unbeknownst to them, Dr. Doofenshmirtz brings the gelatin to life. In "Elementary, My Dear Stacy", Stacy accompanies the family on a trip to London, where she and Candace try again to bust the latter's brothers, in the style of Sherlock Holmes.
In "Don't Even Blink", Candace, her brothers and the rest of the neighborhood build and then watch an invention, hoping to see what happens to it. In "Chez Platypus", the boys construct a trendy new restaurant in their backyard.
In "Thaddeus and Thor", Phineas and Ferb compete with two visiting brothers to build the best treehouse. In "De Plane! De Plane!", the stepbrothers set out to build a plane like what Howard Hughes had built, using papier-mâché.
In "The Baljeatles", Phineas and Ferb help Baljeet prepare to headline a rock concert. In "Vanessassary Roughness", Vanessa tries to prove to her father that she can be responsible enough to have her own car.
The boys travel into the future to borrow a tool, but when their future sister Candace finds what they are up to, she realizes that she has the evidence she needs to travel back into the past to bust her brothers. When she returns to her own time, she realizes that she has made a terrible mistake that only she can fix.
Fans were given the opportunity to vote for their favorite songs from Season #1 and early Season #2 episodes of Phineas and Ferb, and Major Monogram & Doctor Doofenshmirtz put aside their rivalry to host the results on a 1970's-style variety show... or so the doctor would lead us to believe.
Candace learns to drive as she did well with Parell parking. Phineas and Ferb invent a bubble machine and fly across Danville. / After inadvertently accepting to help Phineas on an experiment, Isabella and the rest of the troop get on a mission to find an exotic tree that the boys need to finish it. Meanwhile, Agent Pinky tries to stop Professor Poofenplotz from getting more units of her discontinued hairspray.
After one of Dr. Doofenshmirtz's inventions lands in the yard, the boys try to find out what it does through reverse engineering. / Phineas and Ferb and the neighborhood kids to on an epic journey to find the lost city of Atlantis.
During Christmas vacation, Phineas and Ferb's quest to show gratitude to Santa during Christmas may be doomed for failure, when Dr. Doofenshmirtz uses an invention that puts the entire town of Danville on Santa's naughty list.
After Candace gets trapped inside one of Phineas and Ferb's inventions, she ends up in Patchkinland where she finds out the way to bust her brothers is to see the Wizard in Bustopolis in this "Phineas and Ferb" version of The Wizard of Oz.
In "Make Play", Candace switches places with a princess who looks exactly like her and who helps the boys create a giant jukebox. In "Candace Gets Busted", when the parents go on a trip, they leave Candace in charge of the house. She calls some of her friends for a small get-together. It doesn't end well.