The film's on-screen titles do not display the "The Revenge of Michael Myers" subtitle which was used in all of the promotional material, TV spots, trailers, and merchandise. The main titles simply say "Halloween 5".
Plot:On October 31, 1988, Michael Myers (Don Shanks) is shot and falls down a mine shaft. The state troopers toss dynamite down the mine, but Michael manages to escape in time. He wades into a nearby river and is soon discovered by a hermit. Michael falls into a coma, placing him in the hermit's care. On October 30, 1989, Michael awakens, kills the hermit, and returns to Haddonfield, where his niece Jamie Lloyd (Danielle Harris) continues to live after nearly being killed by Michael the year before.
Jamie has been committed to a children's hospital, having been rendered mute due to psychological trauma suffering from nightmares and seizures, and being treated for stabbing her stepmother under Michael’s influence, but exhibits signs of a telepathic link with her uncle. She senses Michael’s presence and goes into convulsions. Dr. Sam Loomis (Donald Pleasence) becomes aware of Jamie's psychic link with Michael, and tries to convince Sheriff Ben Meeker (Beau Starr) that Michael is still alive. Meanwhile, Michael kills Jamie's sister Rachel (Ellie Cornell) and begins stalking their friend Tina (Wendy Kaplan), also killing Tina's boyfriend Mike.
Later that night, Tina and her friends Sam and Spitz go to a Halloween party at a farm. Sensing that Tina is in danger, Jamie, having regained her ability to speak, goes to warn her; her friend Billy goes with her. While Sam and Spitz are having sex in the barn, Michael murders them, then leaves the barn and kills two deputies that Loomis had asked to keep an eye on Tina for her protection. After the party, Tina goes to the barn and discovers the bodies. Michael chases Tina, Jamie, and Billy with a car. Tina sacrifices herself to save Jamie, and Michael fatally stabs her in the chest. Loomis, Sheriff Meeker, and the police arrive on the scene and rescue Jamie and Billy. Jamie agrees to put herself in danger to help Loomis stop Michael for good.
With Jamie's help, Loomis lures Michael back to his abandoned home. In the old Myers house, Loomis and the police create a set-up. Jamie senses that Michael has arrived at the clinic and Billy is in danger, which causes Meeker, along with most of his backup, to leave the Myers house. Eventually, Michael arrives and kills the two remaining officers. Loomis tries to reason with him, but Michael subdues him and then goes after Jamie.
Jamie hides in an old laundry chute, but she is forced to abandon it after Michael finds her and repeatedly stabs the chute. She races upstairs to the attic where she finds a coffin that was stolen from the cemetery earlier, and the bodies of Rachel, Mike, and Rachel's dog Max. Michael finds Jamie, but before he can kill her, she tries to appeal her uncle's humanity. At Jamie's request, Michael takes off his mask. However, Jamie touches Michael's face, sending him into a fit of rage. Loomis appears, using Jamie as bait, and lures Michael into a trap to weaken him with a tranquilizer gun. After beating Michael unconscious with a wooden plank, Loomis suffers a stroke and collapses. Michael is locked up in the sheriff's station, to eventually be escorted to a maximum-security prison. However, a mysterious stranger in black arrives and attacks the police station, killing the officers, including Sheriff Meeker. Jamie walks through the station, and discovers her uncle's cell empty, prompting her to begin sobbing in terror.
