It's October 30, 1988 and Michael Myers has been in a coma since his pursuit of Laurie Strode, 10 years ago, was finally stopped (events of H1 and H2). However when he is transfered from Richmond Mental Institute to Smith's Grove he awakes when he hears that he has a niece in Haddonfield and after killing the transfer crew he escapes. In Haddonfield, the niece, Jamie, has been adopted by the Carruthers family but keeps having nightmares about Michael (but she doesn't know who he is). On Halloween night, Jamie goes out trick and treating, little knowing that her murdering Uncle is following her and her step-sister Rachel. Rushing to her aid is Dr. Loomis and with the help of Sheriff Meeker starts to search the town for Michael and to find Jamie to protect her. But can anything stop Michael this time?

On Halloween in 1963, Michael Myers murdered his sister, Judith. In 1978, he broke out to kill his other sister, Laurie Strode. He killed all of her friends, but she escaped. A few years later, she faked her death so he couldn't find her. But now, in 1998, Michael has returned and found all the papers he needs to find her. He tracks her down to a private school where she has gone under a new name with her son, John. And now, Laurie must do what she should have done a long time ago and finally decided to hunt down the evil one last time.

The residents of Haddonfield don't know it yet... but death is coming to their small sleepy town. Sixteen years ago, a ten year old boy called Michael Myers brutally kills his step father, his elder sister and her boyfriend. Sixteen years later, he escapes from the mental institution and makes his way back to his hometown intent on a murderous rampage pursued by Dr Sam Loomis who is Michael's doctor and the only one who knows Michael's true evil. Elsewhere a shy teenager by the name of Laurie Strode is babysitting on the night Michael comes home... is it pure coincidence that she and her friends are being stalked by him?