Perry the Platypus (also known as Agent P or simply Perry) is a cartoon bipedal platypus from the American animated series "Phineas and Ferb". Perry was created by the series' co-founders, Dan Povenmire and Jeff "Swampy" Marsh. He first appeared along with the majority of the main cast in the pilot episode "Rollercoaster". Perry is featured as the star of the B-plot for every episode of the series, alongside his nemesis Dr. Heinz Doofenshmirtz. A mostly silent character, his lone vocal characteristic (a rattling of Perry's beak) was provided by Dee Bradley Baker.

Perry was made a platypus because of the animal's striking appearance and the lack of public knowledge of the animal, which allowed the writers to make things up about the species. Critical reception for the character from both professionals and fans have been considerably positive.

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