The theme was composed and performed by director John Carpenter for Halloween, released in 1978, after he decided to score the low budget film himself. Its simple piano motif became closely linked to masked killer Michael Myers and helped define the slasher sound of the era. The music returned across sequels and remakes and later spread online as a shorthand for stalking, suspense and anything creepy. It remains a staple every October and in horror edits year round because audiences recognise its meaning immediately.