Hey, knock it off is a common English idiom used to tell someone to stop annoying, noisy or disruptive behaviour, and the short spoken form has become a handy reaction clip online. Without a single famous source attached to this exact recording, it circulates as a general meme sound rather than a quote from one film or show. Its appeal is its clarity: anyone hearing it instantly understands the speaker is fed up, which makes it easy to reuse across comedy edits, gaming clips and short-form videos where a quick scolding is funnier than a long explanation.