Halloween 1963; a young and violently unstable Michael Myers takes a brutal revenge on his uncaring and abusive family, butchering his stepfather, his elder sister and her boyfriend. The next 17 years sees the increasingly withdrawn Myers imprisoned in Smith's Grove Sanitorium under the care of Dr Sam Loomis until, one night, Michael escapes and heads home to Haddenfield and to the one person he ever cared about, his baby sister Laurie.