It's the last day of summer vacation and Phineas and Ferb decide to seize the day and make the most of it. Unfortunately for Candace this means it's also her last chance to bust her brothers... or is it?
After facing the choice of imprisonment or community service, Doof becomes a teacher at Vanessa's school. Meanwhile, a trio of bugs embark on a journey to become the first insects to communicate with humans.
After Doofenshmirtz is defeated, a new threat in the 2nd Dimension emerges, leaving it up to Phineas, Ferb, Candace and her resistance fighters to defeat this new foe.
Doofenshmirtz's latest "inactor" turns Danville citizens into contagious zombies. Agent P. and the gang try to save the town and avoid becoming zombies themselves.
Doofenshmirtz teaches an Inator Method seminar.
Doofenshmirtz gets kidnapped by Professor Mystery. Phineas and Ferb find a capsule with Bernie and Denise.
In a parallel universe far, far away, Phineas and Ferb are tasked with returning the Death Star plans to the Rebel Alliance before Storm trooper Candace catches up to them. Meanwhile, complications arise when Perry is trapped in carbonite.
Candace is accidentally hit by the Impersonator-inator which changes her appearance to a pizza delivery guy, but uses this appearance to help her better understand boys.
Isabella unintentionally admits her feelings for Phineas in a letter. Meanwhile, Doof invents an inator to help change his misfortune
Phineas and the gang help Love Händel prove the existence of Klimpaloon, the magical old-timey bathing suit that lives in the Himalayas, to verify that their song, "The Ballad of Klimpaloon", is legitimate.
Buford and Baljeet get in a food fight while Ferb is at the dentist. The Fireside Girls help Isabella plan a romantic picnic with Phineas. Meanwhile, Vanessa wants to go to a movie marathon, so Doofenshmirtz creates a Teleport-inator.
Doof gets rogue OWCA agent Dennis the Bunny to escape prison. Meanwhile, Phineas and Ferb make some improvements on the Fireside Girls' marionette show.
Perry helps Doof in retrieving his father's old lawn gnome. Meanwhile, Phineas and Ferb help out their father on Father's Day
Doof's latest inator changes the way the Earth moves and it is up to Phineas and the gang to save summer.
When Candace is accidentally zapped by Doofenshmirtz’s Stinkelkrampen-Inator (aka Good Luck-Inator), she realizes she has a good chance of busting Phineas and Ferb.
Candace brings her plush Ducky to life. Doofenshmirtz encounters a Giant Floating Baby Head. Phineas, Ferb, and their friends confront a horde of evil platypuses.
Phineas and Ferb deejay at Vanessa's Halloween party. Doofenshmirtz hunts for hidden treasure in a castle.
The gang switches bodies with alien tourists for a free intergalactic vacation.
Candace and Stacy compete in Phineas and Ferb’s Ultimate Obstacle Course. Doofenshmirtz plans to humiliate his brother, the Mayor.
When Linda becomes overwhelmed for organizing a block party, she asks Phineas and Ferb for help. Norm falls in love with Rodney's female robot.
Phineas and the gang celebrate Isabella's birthday in a big way, but all she really wants is some quiet time with Phineas. Meanwhile, Doofenshmirtz has installed his Bugs Me-Inator onto an evil bug bus and is driving around Danville turning all the things that bug him literally into bugs.
Phineas and Ferb build a wall for climbing. Candace is recording a Fireside Girls book with Irving and loses her voice. Meanwhile, Dr. Doofenshmirtz creates the Just-Desserts-inator.
Candace thinks she can trap the boys at last when they ask her to call Mom if they get stuck in their giant Gordian Knot, but is distracted by helping Jeremy open his mini-safe.
Dr. Doofenshmirtz and Major Monogram have their hearts set on revealing the top 10 musical numbers from Seasons 2 and 3, but soon find out that celebrity host Kelly Osbourne has been brought in to fill the role. Unwilling to submit to playing second fiddle, Doofenshmirtz makes it his mission to thwart Kelly until Perry the Platypus sets out to stop his nemesis from ruining the entire show. Maia Mitchell ("Teen Beach Movie") also guest stars.
Isabella and the Fireside Girls turn themselves into bees. Poofenplotz tries to become Queen of the World by stealing and consuming massive amounts of royal jelly.
The boys make a giant inflatable wading pool for Mom. Candace reveals her "Emo" side. Doofenshmirtz attempts to become ruler of all bees.
The boys create a new invention using recycled parts from past projects. When Candace attempts to bust them, Mom is too exhausted from baking pies all night and can't figure out what Candace is trying to show her.
The gang switches bodies with alien tourists for a free intergalactic vacation.
Perry comes face to face with an Australian platypus hunter set on destroying him. Baljeet is having an existential emergency and finds himself incapable of making decisions.
Agent P teams up with an estranged former human partner named Lyla to stop a hijacked train to save the train's passengers and Canada's national treasure - a moose named Albert.
The boys create Rutabaga-themed vehicles when Candace is chosen to be Rutabaga princess and gets to start the "Running of the Chinchillas." Across town, Doofenshmirtz plans to turn himself into a real live Kinderlumper to scare Roger into relinquishing control of the Tri-State Area over to him.