"Perry the Platypus" is a background theme song played as Agent P embarks on a mission to stop Dr. Doofenshmirtz. It was mostly run in small fragments until "One Good Scare Ought to Do It!" when it was run in the form of a full song with a montage. It was heavily voted for as a favorite to be showcased in "Phineas and Ferb Musical Cliptastic Countdown" but did not make the final cut.