Perry the Platypus , A.K.A. Agent P, is Phineas and Ferb's pet platypus .
Perry lives a double life as a crime-fighting secret agent working for the "Organization Without a Cool Acronym" (The O.W.C.A.), going by the codename "Agent P."
He reports to his superior, Major Monogram, via telecast in his large, high-tech, underground hideout. Everyday, he engages in battles with the evil mad scientist Dr. Heinz Doofenshmirtz, who tries using inventions to take over the tri-state area. Perry is always able to foil Doofenshmirtz's plans and in doing so accidentally leads to the destruction of whatever form of contraption his owners, Phineas Flynn and Ferb Fletcher, are building in order to make summer better.Phineas and Ferb are aware that something happens to get rid of their scheme for the day, but do not know that Perry is the cause behind it and are largely dismissive of it. Their sister, Candace, also does not know that Perry is behind the destruction and is driven to near insanity trying to figure it out.
Perry is aware of Phineas and Ferb's inventions, but is uninterested in them.
Perry still working for O.W.C.A and still foiling Doofenhenshmirtz's plan, while remain intake as the boy's pet animal even their world were conquered and currently live in the Safe House somehow.