
Phineas Flynn and his stepbrother, Ferb Fletcher, are determined to make every day of their summer vacation fun. They try building a full-scale roller coaster, becoming musicians, building a backyard beach, and traveling back in time to meet dinosaurs. Their family pet, Perry the Platypus, doubles as a secret agent and battles evil. Meanwhile, older sister Candace is tattling on them to Mom and Dad, though she can never seem to catch them in the act.

Doof gathers energy from people exercising while the kids pilot a boat that surfs concrete; Candace and Jeremy make a Perry documentary as the kids play an extreme game of croquet.

Vanessa and Monty bring their warring fathers, Doof and Monogram, to a "meet the parents" dinner; Buford goes on a whimsical adventure with a bread bowl hot tub.

Monogram and Carl inspect Agent P's many lair entrances while Candace tries to speak to the Mysterious Force; the kids go on a dungeon crawl while Doof tries a reality dating show.

The kids build a giant submarine sandwich submarine while Doof steals food; Candace tries to bust the boys while taking her driving test; Doof causes chaos in traffic.