Laurie, having being taken to Haddonfield memorial hospital for her stab wounds has flash backs from her childhood and realises she is Micheals sister.
Meanwhile, Dr Loomis and the serrif are on the hunt for Myres, Loomis's nurse Marion tells Loomis that he must return to Smiths grove and informs him of the fact that Laurie and Micheal are in fact, brother and sister. They make thier way to the hostipal.
Micheal, however is already there, and begins killing off the hostpital staff one by one, including mr. Garrett, the night watchman, Bud the ambulance driver, nurses Jill, Karen, Janet, and Mrs. Alves, and even the drunken Dr. Mixter, the only people left are Laurie and the young porter Jimmy, who finds the body of mrs Alves and slips on her blood when trying to get help.
Laurie realises she is next and escapes outside the hospital and hides in Jimmys car, but with the shape hot on her heels she has to return to the hospital.
Meanwhile, Dr Loomis and nurse Marion arrive at the almost deserted hospital to find Myres, Loomis shoots Myres down, and tells Marion to get help while he finds Laurie.
Laurie meanwhile having been chased into the operating room is cornered by the shape, when Loomis comes to her rescue by shooting Myres in the eyes, blinding him, in the suspenseful scene that follows, Micheal and Loomis are blown up in the hospital, we see Micheal burn, Laurie and Jimmy go off in an ambulance.
