The line comes from the 1999 thriller The Sixth Sense, written and directed by M. Night Shyamalan. Child character Cole Sear, played by Haley Joel Osment, whispers it to psychologist Malcolm Crowe, played by Bruce Willis, revealing that he sees ghosts. It became one of the most quoted movie lines of the era and was widely parodied in comedy, horror edits and Halloween content. Online it survives as shorthand for spotting something creepy, uncanny or long forgotten, which keeps the clip in constant rotation as a reaction sound.