Perry the Platypus is the seemingly ordinary pet of Phineas and Ferb in the Disney animated series Phineas and Ferb, which began in 2007. Beneath his quiet pet routine, Perry is also Agent P, a secret agent who battles the villain Dr. Doofenshmirtz, and his distinctive chattering noise became a running gag for fans. Clips of that noise spread through meme pages, reaction videos and soundboards, where it now works as shorthand for a hidden identity or a sly, knowing moment. Its short length keeps it easy to drop into edits.