Provider: Eastern (ET) Change
Ferb's cousin visits from England, so the boys build a soccer stadium to play in. Meanwhile, Candace tries to learn better etiquette to help her relationship with Jeremy; and Doofenshmirtz builds a device that makes any falling tree say his name.
Phineas and Ferb create a language; potato gremlins appear all over town after the guys clone a potato chip from Buford and it mixes with his DNA; Doofenshmirtz tries to summon the Spartan army with his historical army retrieve-inator.
Phineas and Ferb are turned into babies by Doofenshmirtz's "Babe-inator," but the crazed doctor soon decides to give up his evil ways and join Perry as an agent for good; the guys help a damsel in distress find her missing mother in Central America.
Perry disappears so Phineas and Ferb create a mechanical device that can assume any form to find him; Doofenshmirtz duplicates his own head so he will be twice as smart; the guys create a colorful fall world, and Doofenshmirtz mentors a student.
Phineas and Ferb put on a backyard magic show; the guys help their dad unearth a missing piece of Danville history; Doofenshmirtz tries to make himself younger to win a children's film festival.
Perry tries to escape from an Australian platypus hunter who wants to destroy him. Meanwhile, Phineas and Ferb create a device that enables Baljeet to make as many choices as he pleases without suffering any consequences.