Episode Title:Undercover Carl - Hip Hip Parade.Episode Description:Undercover Carl: When the boys build an Anti-Gravity Fun Launcher, Carl accidentally discovers their plans on the internet and presumes they are working for Dr. Doofenshmirtz, so he is sent undercover to figure out what they are doing. Meanwhile, Doofenshmirtz intercepts the plans himself and attempts to find a use for it, and Perry is sent on a literal wild goose chase to retrieve a missing agent since he is too close to the boys to spy on them.
Hip Hip Parade: Phineas and Ferb decide to help build floats for all the neighborhood kids in the yearly "Tri-State Area Unification Day" parade, but a family grudge leads Buford to try to wreak havoc on the parade. Candace promises her mom to not care about Phineas and Ferb's activities during a mother-daughter day, but finds it difficult due to the boys' antics taking place all around her. Meanwhile, Dr. Doofenshmirtz tries to create traffic jams with a duplication device.[1]