Picking up where the previous film left off, Mike Pearson escapes Boulton mortuary in a hearse, while Reggie is trapped by The Tall Man's spheres. Rather than kill Reggie, the Tall Man releases him, telling Reggie their final "game" begins. Mike's brother Jody, still a black sphere that can occasionally resume his human form, contacts Reggie to search for Mike. On his way, Reggie survives a demon attack, and rescues a woman named Jennifer from a car accident.
Meanwhile, Mike tries to escape his transformation, driving through abandoned areas, recalling the last days of his youth before The Tall Man's arrival. After seeing visions of the elderly Fortune Teller he consulted years ago, the Tall Man appears, declaring he is taking Mike "to prepare for passage." Mike is taken to Death Valley, where he attempts suicide by hanging. However the Tall Man intercedes and shows him conflicting memories of when he and Jody attempted to kill the Tall Man years ago. Forbidden from taking his own life, Mike sees the Tall Man offer his hand, implying he wishes to guide him. Refusing, Mike escapes through a dimension fork, which takes him back in time.
Mike emerges from an early version of the gateway in an 1860s era laboratory. There, Mike is greeted by a kind man, Jebediah Morningside, an elderly scientist and creator of the gate who looks exactly like the Tall Man. Mike is frightened away after seeing Jebediah and that the Fortune Teller is mysteriously present. In the desert, Mike realizes he is slowly developing telekinesis when he kills a dwarf with a large boulder. Jody appears to him, but a distrustful Mike accuses him of abandoning him. Mike begins working on the hearse's engine, using parts to build a makeshift sphere. Meanwhile, Reggie and Jennifer stay at an abandoned motel, where he tells her about The Tall Man. Jennifer is soon revealed to be one of his minions, with two spheres in place of her breasts. Reggie manages to fight her off and kill her.
Mike goes through a gate, finding himself in a deserted city where he escapes the Tall Man, with Jody's help. Reggie arrives at Death Valley and fights off a group of dwarfs, shortly before Mike and Jody reappear. Mike warns Reggie not to trust Jody before departing yet again. Mike and Jody pass through the gate to Jebediah's house. Invisible to the old man, they witness him approach the inter-dimensional gate to learn the secrets of the world of the dead. Mike unsuccessfully tries to stab Jebediah, who vanishes and moments later is replaced by the Tall Man incarnation who emerges in his place. Mike escapes through the gate again, and Jody attacks him under the Tall Man's thrall.
Awakening on an embalming slab, Mike uses a tuning fork to immobilize Jody and the Tall Man as they attempt to cut open his head, before making the Tall Man kill Jody. The Tall Man quickly revives and pursues Mike to Death Valley. Reggie tries to shoot the Tall Man, but is overpowered. Mike summons the sphere he created and impales The Tall Man's neck, before activating the hearse's motor to explode, seemingly destroying him before a new Tall Man immediately comes through the gate, and removes the golden sphere from Mike's head, before departing. While Reggie goes on to pursue the Tall Man. Left to die, Mike recalls a childhood memory where Reggie gave him a ride; they both hear their future exchange before Reggie's departure. The younger Mike brushes it off, declaring "it's just the wind."
Canadian filmmaker Roger Avary, a self-professed hardcore fan of the Phantasm series, wrote an epic screenplay titled Phantasm 1999 as a sequel to Phantasm III: Lord of the Dead. It was set in a post-apocalyptic near future and would feature Bruce Campbell as a co-star. As the project ran into financing difficulties, Don Coscarelli wrote and directed Phantasm IV: Oblivion as a precursor to the project, using numerous outtakes from the preceding films. Avary also appeared in the film as one of the Civil War soldiers. Despite these efforts, the budget for the sequel, now retitled Phantasm's End,
Reception
On the review aggregator website Rotten Tomatoes, 29% of 7 critics' reviews are positive.
Jeremiah Kipp of Slant Magazine gave Phantasm IV: Oblivion a mixed review, awarding it a two out of four-star rating, and writing: "The freewheeling atmosphere of dread more than make up for the incoherence, but Phantasm IV: Oblivion at times feels like an expensive, 35mm home movie made by some kids in their backyard."
