Elmo is the red, furry Muppet from Sesame Street, a character audiences have known for decades as friendly, curious and childlike, which is exactly why a threatening line in his voice works so well as a joke. The knows-where-you-live version circulates online as a short prank and meme sound, shared in edits, reaction clips and short-form videos where creators play on the gap between Elmo's innocence and the sinister message. That contrast keeps it useful for Halloween content, prank calls and surprise endings, because listeners instantly recognise the voice before they register the threat.