Who is the villain of the "Halloween" horror movies?

The villain of the "Halloween" horror movies is Michael Myers. He is the masked, nearly silent killer who returns to Haddonfield, Illinois, beginning with the original 1978 film.

In John Carpenter’s Halloween, Michael murders his teenage sister Judith as a child, is confined to Smith’s Grove Sanitarium, and escapes 15 years later. He then stalks babysitter Laurie Strode, played by Jamie Lee Curtis. His blank white mask, dark coveralls, and slow, relentless movement became defining images of the slasher genre.

Michael is often called "The Shape," a name used in the original film’s credits. Different timelines and reboots change details about his family, motives, and possible supernatural qualities, but Michael remains the central antagonist in almost every entry. The notable exception is Halloween III: Season of the Witch (1982), which tells a separate story about Silver Shamrock masks and does not feature him.