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 the blast. He stumbles 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 attacking her foster mother under Michael’s influence, but exhibits signs of a telepathic link with her uncle. 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) by stabbing her in the chest with scissors and begins stalking their friend Tina (Wendy Kaplan), also killing Tina's boyfriend Mike with a sharp rake to his head.
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. Spitz is impaled with a pitchfork and Sam is sliced across the chest with a garden scythe. Michael 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 Sheriff 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.
The success of Halloween 4: The Return of Michael Myers had revived Michael Myers' fame as the 1980s slasher movie craze had begun to subside; 1980s-started film series like Friday the 13th and A Nightmare on Elm Street were also in decline. While the previous film was still in theaters, Moustapha Akkad had already laid out plans for Halloween 5. The producers wanted to screen the film in October 1989, just one year after the previous sequel.
The first draft of the script was written by Shem Bitterman. Bitterman's idea was that Jamie Lloyd would become evil after stabbing her stepmother while The Shape was after her. This idea was rejected by the studio and Akkad, who brought in Michael Jacobs to write the script. After reviewing the script, director Dominique Othenin-Girard edited it to create new scenes for more violence.
Veteran actor Donald Pleasence had disagreements with Akkad and Othenin-Girard, citing that Jamie should have been portrayed as "all-evil" after stabbing her stepmother. Akkad disagreed, thinking that fans wanted to see more of The Shape. In an interview, Danielle Harris explained what she thought of the idea. Harris said,
The way Halloween 4 ended, I thought I was going to be the killer. I thought it would have been fun to come back as the killer, or Michael's sidekick. Scary, but fun.
Halloween 5 was rushed into production on May 1, 1989 before the existence of a solid script. The script was filmed without perfections and many suspenseful scenes, such as Tina and Samantha doing cart-wheels near The Shape, were cut to less suspenseful scenes.
Originally, Rachel was supposed to be killed by having scissors shoved down her throat. Ellie Cornell, who played Rachel, did not like the idea and requested it be changed to simply being stabbed with the scissors.
The Hermit, who was shown in the beginning of the film as living in a quiet shack outside of the river with his parrot, was originally supposed to be a young man, named 'Dr. Death' in the script, who tried to bring The Shape back to life after finding him. His shack was supposed to be filled with ancient runes, tablets, and other items for resurrection. This scene was filmed, but was re-shot with an old man, instead of a younger man. The scythe that was supposed to kill Samantha was originally going to go through her forehead.
The scene where Michael Myers drives a car while wearing a different kind of mask was initially scripted to have him wear a Ronald Reagan mask. However, the idea of a Reagan mask was soon rejected in order to keep the film devoid of any political subtexts.
The script included "bumbling" cops, Deputies Nick and Tom, with their own "clown theme" to pay homage to Wes Craven's The Last House on the Left.
Returning from Halloween 4 was veteran actor Donald Pleasence as Dr. Sam Loomis, along with Danielle Harris, Ellie Cornell, and Beau Starr, as Jamie Lloyd, Rachel Carruthers, and Sheriff Ben Meeker, respectively. Starr would later appear in an un-aired Halloween 5 television spot.
Karen Alston, who portrayed Darlene Carruthers in the previous film, reprised her role in the beginning of the film showing the anonymous person in the mask stabbing her as she falls into the bathtub of water. Her voice-over was recorded by Wendy Kaplan. Kaplan won the role of Tina Williams, the loud and wily friend of Rachel's. After Rachel's demise, Tina inherits the role of Jamie's protector.
George P. Wilbur, who had portrayed The Shape in the previous film, did not express interest in returning to play the role (although he did work as a stunt player on the film). Don Shanks was cast to play the speech-less, white-masked murderer. Shanks had already played a similar character in the first two Silent Night, Deadly Night films. Shanks also played the Man in Black. Wilbur, who had to wear hockey pads to appear to have a bigger build, would later portray the Shape again in the next installment, Halloween: The Curse of Michael Myers. Shanks did not have to wear the hockey pads because he already had a larger build.
Max Robinson would play Maxwell Hart, the doctor who assists Jamie when she is having one of her nightmares in the beginning of the film. Betty Carvalho appears as his assistant, Nurse Patsey, who has a "motherly" feel to Jamie. Jeffrey Landman portrayed Billy Hill, Jamie's best friend, who has a stuttering problem. Landman worked with a coach who taught him about stuttering to help him prepare for the role.
Newcomers such as Tamara Glynn, Matthew Walker, and Jonathan Chapin appear as Samantha Thomas, Spitz, and Mike, who are friends of Tina and Rachel. Walker would later appear in another slasher film, Child's Play 3 (1991).
Debra Hill, who had written and produced the first two films, had sold her and John Carpenter's rights to the series before Halloween 4. She had met director Dominique Othenin-Girard at the Sundance Film Festival and liked his style.
She arranged a meeting with Othenin-Girard and Moustapha Akkad. Akkad liked Othenin-Girard and he became the director. This was Debra Hill's last involvement in the series. Othenin-Girard wanted to bring the series closer to the original, but wanted more blood in the film. The original uncut version of the film featured more explicit gore and violence. Akkad did not like this decision, as he felt that the original and Halloween 4 had worked better without showing as much detail.
After filming for two weeks, Donald Pleasence gave his much bigger trailer to Danielle Harris once he left set. Harris's mother had been complaining about the small size of her daughter's trailer and Pleasence decided that she should have his.
Danielle Harris and Don Shanks became good friends over the course of filming, reportedly spending a lot of time together while off set.
The film began production on May 1, 1989, and was filmed in and around Salt Lake City, Utah, just like its predecessor. The bus that the Man in Black gets off of stops outside exactly the same store where Jamie and Rachel went to get a Halloween costume in Halloween 4: The Return of Michael Myers.
Unable to find a small Victorian house like the Myers House in Halloween, the filmmakers chose a bigger, more mansion-like house because they needed a house that could provide wide rooms, hallways, an attic, a basement, and a laundry chute. Donald Pleasence accidentally broke Don Shanks's nose on the set when they were filming the scene where Dr. Loomis beats The Shape with a 2×4 block of wood.
Don Shanks was also injured when he was filming the scene where The Shape crashes Mike's Camaro into the tree. Dominique Othenin-Girard had forgotten to yell "Cut!" and fire was beginning to emerge from the car (Shanks put this down to Othenin-Girard being sidetracked by seeing stunts take place during his first major directing job). Finally, stunt coordinator Don Hunt told Othenin-Girard to finally yell "cut". Wendy Kaplan was also injured in this scene, as the car almost ran over the top of her. She was uninjured as seen in Halloween: 25 Years of Terror.
Gregory Nicotero and Wendy Kaplan were seeing each other during filming.
The film had been fighting an X rating due to its violence, blood, and gore. Some scenes were trimmed down to keep it rated R, including a shot of Mikey quivering on the ground after Michael stabs him in the head with a garden fork, a shot of glass embedded in Officer Eddy's face after Michael punches through the windshield, and Billy's leg being hit by the Camaro.
In the scene in which Jamie climbs up the laundry chute, she was originally supposed to be stabbed in the leg, sending a splash of blood into the camera. The aftermath can be seen when Jamie gets out of the chute: a bloody stab wound is clearly visible on her right leg, and she walks with a noticeable limp. Danielle Harris wore a prosthetic leg for the filming, which she still owns.
An alternative opening was filmed with the Hermit replaced by a younger, hippy-like man named 'Dr. Death' with all kinds of ritualistic items in his cabin. This scene can be seen on Inside 'Halloween 5'.
More scenes with the character of Billy were filmed, but were cut. The scenes include Billy meeting Rachel and Tina for the first time on his bicycle with Max the dog, Jamie telling Billy to follow Tina to the Tower Farm, and a scene showing Billy being rushed into the children's clinic, while the police find the body of Dr. Hart.
KNB Effects had designed grotesque facial makeup for Michael Myers' unmasking toward the end of the film. The producers told them to do so as an option, either showing Michael's badly scarred face, or keep it in the dark. They went for the latter.
On Rotten Tomatoes the film has a 14% "Rotten" approval rating based on 22 reviews. Despite the reception for the film, Danielle Harris and Donald Pleasence received praise for their performances.
The film has been released on VHS, LaserDisc and DVD. The original VHS was released by CBS/FOX. It has been released, along with Halloween 4, on Divimax, disc one of the 25 Years of Terror documentary and the Blu-ray, DVD and "extended edition cut" of the original Halloween in 2008 for the Halloween: 30th Anniversary commemorative box-set. A Blu-ray release for the US took place on August 21, 2012. The DVD release is THX certified. With the exception of the original VHS, Anchor Bay has handled all subsequent releases. The film was released on DVD/Blu-ray on October 2, 2013 in Australia and the DVD/Blu-ray extras are commentary, on the set footage and trailer.