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?

Professional killer Gav Reed commits a grave mistake allowing himself to be videotaped (as she always does...