Phineas and Ferb decide to do absolutely nothing for the day. Candace questions her purpose in life after realizing that she can't bust her brothers for doing nothing. Meanwhile, Dr. Doofenshmirtz is tired of being the ugliest person around, so he invents a device that can turn anything and anyone ugly.

Phineas and Ferb create the world's largest golf course, and since Candace is sick, she asks her best friend Stacey to bust the boys for her.

The boys learn about one of Ferb's Victorian ancestors, who helped a scientist create a monster. Meanwhile, Doofenshmirtz recalls the story of his great-great-grandfather Dr. Jekyll Doofenshmirtz.

The boys create a cartoon and cast themselves as superheroes and Candace as the villain, while Perry attempts to defeat Doofenshmirtz, who has taken control of the power of dance.

When Candace believes that no one wants to be around her anymore, she quickly steps through Baljeet's portal to Mars, where she is quickly heralded among the martians. Meanwhile, Perry accompanies Dr. Doofenshmirtz to help build his evil contraption for him to stop faster, with slightly less than pleasing results.

After taunting the boys for going to search for the "Lake Nose Monster", Candace begins freaking out on her lifeguard job, seeing the monster at every turn. Meanwhile, Dr. Doofenshmirtz tries to remove all the zinc from the lake, though even he's not sure why.

The boys decide to spread the word about the tip of the shoelace, called the "aglet." Meanwhile, Doofenshmirtz is featured in the newest viral video to hit the internet.

Phineas and Ferb create a slow reacting growth potion to help Baljeet with his "giant" watermelon, but Candace decides to use it for herself, when she finds that she's a little too short to be a flawless girl. Meanwhile, Perry must stop Doofenshmirtz from his most disgusting plan ever!

It's another average, logic defying day for Phineas and Ferb, until a crashed space pod, carrying an unbearably cute alien, Meap, thrusts the boys into another adventure in space! Everyone has a different role to play, while Candace holds on to Meap by accident, Ferb is fixing up the ship, as Phineas uses the new cute tracker to find where their new friend is, to the slight irritation of Isabella, as he can't get what *cough* is causing cute interference, but of course, it all has to lead up to the big explosive finale in SPACE -ace-ace. Meanwhile, Doofenshmirtz has a new plan, simplistic in nature, but buried in an avalanche of backstory, oh dears.

Phineas and Ferb learn that Baljeet has signed up for rock camp and worries he may get his first failing grade. So the boys help by forming a band to help him express his feelings, especially for math. Meanwhile, Candace wonders why Jeremy doesn't give her a cool nickname as Stacy gets close to Coltrane, the rock camp director. Doofenshmirtz's latest plan has him wanting his own army of babies by broadcasting his heartbeat all over the tristate area.

The boys reconstuct one of Doofenshmirtz's inventions to discover what it does after it lands in their front yard.

Phineas and Ferb are decorating their city for the arrival of Santa Claus. But when the evil mad scientist Dr. Heinz Doofenshmirtz uses a machine to ruin the holiday, Phineas and Ferb must find a way to fix it and save Christmas.

Khaka Peü Peü arrives in Danville to challenge Phineas and Ferb after the boys are mistaken as a superhero (while wearing an indestructible suit they designed to safely conquer their newly built extreme skate-track) known as The Beak. With the super villain wreaking havoc, it's up to Phineas and Ferb to thwart him while Dr. Doofenshmirtz tells the people of the Tri-State area that he is in charge, in hopes that they will actually just go along with it. Meanwhile, his brother Roger is worried that everyone will blame him for the recent super villain catastrophe so he decides to make Doofenshmirtz Mayor.

Phineas and Ferb head to the Tri-State area’s annual sci-fi/comic book convention to meet their hero, special effects guru Clive Addison. Their plan gets sidetracked when they’re swept into a duel between fantasy fans and sci-fi geeks. Meanwhile, Candace tries to keep secret that she’s a fan of Ducky Mo-Mo, another convention staple. Across the convention hall, Dr. Doofenshmirtz has taken television executive Jeff McGarland hostage so he can pitch him a show he’s developed, Doof ‘N’ Puss.

When Ferb's cousins visit from England and challenge him to a soccer match, he and Phineas warp the walls of physics and build a high tech 3D stadium. Meanwhile, convinced that her relationship with Jeremy depends on her being more proper, Candace enlists the help of Ferb's British cousin, Eliza, to teach her the rules of etiquette. Back at Doofenshmirtz Evil Inc., Dr. Doofenshmirtz is sick in couch but forces himself to set off his \"If-A-Tree-Fell-in-the-Forest-Inator\", which causes any tree that falls to say his name.

Meap's world is put in danger and the boys try to help him save the universe when they travel to Seattle. Meanwhile, Doofenshmirtz visits former nemesis Peter the Panda.

With Fall around the corner, Phineas and Ferb decide to invent "S'Fall", a colorful world full of giant leaf piles and gourds. Meanwhile, over at Evil Inc., Dr. Doofenshmirtz is mentoring Rodrigo, a budding student of evil. Unfortunately, Rodrigo truly is evil, and when he captures Dr. Doofenshmirtz and Agent P., it’s up to Major Monogram's son, Monty, to save the day.

Agent P's fate is finally revealed in the action-packed finale of the two-part television special that left Phineas, Ferb and the gang hanging...literally off an unchartered gorge and Candace frantic over a phone call with Jeremy that left their relationship status in limbo. Now, with Agent P nowhere in sight, Dr. Doofenshmirtz and Major Monogram square off against evil Carl who controls a set of familiar-looking robots to take over the OWCA, in one of the biggest battles yet.