Phineas and Ferb season 4

The fourth season of Phineas and Ferb first aired on Disney Channel on December 7, 2012, and December 31, 2012, on Disney XD. The series centers on stepbrothers Phineas Flynn and Ferb Fletcher trying to make every day of their summer vacation the best ever, while their older sister Candace Flynn tries to bust them. Other main characters include secret agent Perry the Platypus (who is also Phineas and Ferb's pet) and the evil scientist Dr. Heinz Doofenshmirtz. The episode of “Doof 101” was initially meant to be a pilot for a spin off series titled after it which was to be about Dr. Doofenshmirtz becoming a high school teacher; however, it was not picked up for some unknown reason. This was the final season of the series until it was revived in 2023 with two additional seasons.