The music comes from Halloween, John Carpenter's 1978 horror film, where the piano theme became inseparable from Michael Myers, the masked killer who stalks Haddonfield. Carpenter composed the score himself, and its simple, relentless rhythm helped define the slasher genre's sound. Over decades, the theme has been reused in sequels, trailers, parodies and fan edits, turning it into shorthand for approaching danger. Online, creators borrow the short motif to signal that something threatening is near, even in comedic or everyday videos.