Phineas und Ferb feiern den S'Herbst, indem sie einen riesigen Laubhaufen bauen, in den sie reinspringen wollen. Währenddessen hilft Major Monograms Sohn Perry dabei, Doofenschmirtz und seinen bösen Praktikanten Rodrigo zu besiegen.
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.
Phineas, Ferb og gjengen feirer s’høst ved å lage en diger løvhaug å hoppe i, mens Major Monograms sønn hjelper Perry med å bekjempe dr. Doofenshmirtz og hans onde elev, Rodrigo.
Le Major Monogram a un fils du nom de Monty...
