A film editor gets embroiled in a string of murders.
Rey Ciso was once the greatest editor the world had ever seen. Since a horrific accident left him with four wooden fingers on his right hand, he's had to resort to cutting pulp films and trash pictures. When the lead actors from the film he's been editing turn up murdered at the studio, Rey is fingered as the number one suspect. The bodies continue to pile up in this absurdist giallo-horror as Rey struggles to prove his innocence and learn the sinister truth lurking behind the scenes.
Film editor Rey Ciso works on cutting filmmaker Francesco Mancini's latest giallo movie "Tarantola" with his attractive assistant Bella. Once a master craftsman, Rey lost his fingers and is now handicapped by a wooden hand. After an encounter at the studio with the film's lead actor Claudio Calvetti, Rey goes home to his wife Josephine Jardin, a once-prominent actress who berates her husband while fantasizing about Claudio.
An unknown killer murders Claudio while he has a private screening of the "Tarantola" workprint with his girlfriend Veronica. Actress Margarit Porfiry goes blind from hysteria after finding the body. Her police inspector husband Peter interviews studio employees with the help of an officer named Giancarlo. Actor Cal Konitz's hopes of having an increased role in the movie are dashed when Francesco introduces Cesare, a lookalike stand-in for Claudio.
Police Chief O'Connor pressures Porfiry into closing the case because Margarit is his daughter. Porfiry begins suspecting that Rey is the killer, since Claudio's fingers were severed in the same manner as Rey's right hand. Porfiry goes to Francesco's estate for an interview and learns that Rey was once in an asylum. After Porfiry leaves, Rey's wife Josephine descends Francesco's staircase in a negligee. At church, Rey receives confession from Father Clarke.
Back at the studio, Cesare is murdered in the shower and his fingers are severed. With Cesare dead, Francesco instructs Rey to re-cut the film to make Cal the new star. Porfiry asks Rey about his time in the asylum. Rey recalls how he earned his start in the business, leading to an award for editing "The Mirror and the Guillotine," which was also where he met Josephine. When his wife was fired by Francesco on the next picture, the pressures of editing the world's longest film mounted and Rey cut off his own fingers in a fit of madness.
Cal introducers Porfiry to his girlfriend Jasmine Rain. Porfiry reveals that he and Jasmine were once lovers. Porfiry is oblivious to the bladed instruments Cal places in the trunk of his car.
Rey returns to work in the editing suite with Bella. She confesses to being in love with Rey, but Rey resists the attraction between them because he is married. Rey goes out to dinner with Josephine and they have an argument. Porfiry interrupts. Later that night, Rey has a vision of someone stalking him from the shadows in his bedroom.
Porfiry infiltrates the Pilgrim Psychiatric Asylum to search for patient records on Rey Ciso. After an encounter with an inmate who tries seducing him, Porfiry meets Dr. Alberto Casini, who previously treated Rey. Casini tells Porfiry about his first meeting with Rey, when he was an up and coming editor who almost killed his assistant Giuseppe. Casini tells Porfiry the parable of Plato's cave and shows him that Giuseppe is now an inmate whose head is mysteriously wrapped in bandages.
Porfiry returns home to find that Margarit now has a seeing-eye German Shepherd named Ralphie. The killer breaks into their home and tricks Porfiry into putting an ax blade into Margarit's head. Porfiry cuts off Margarit's fingers and feeds them to Ralphie to make it look as though Rey Ciso killed her. Giancarlo arrives and Porfiry confuses him into supporting false facts about the murder.
O'Connor berates Porfiry over Margarit's death. The killer calls Porfiry at the station and taunts him. Porfiry convinces O'Connor into supporting a plan where Giancarlo goes undercover as the new editor at Francesco's studio.
Francesco fires Rey and replaces him with Giancarlo. Rey goes home to find Josephine watching Cal's demo reel. Rey begins having strange, otherworldly visions involving Bella. Meanwhile, Bella is killed in the editing room. While trying to finish "Tarantola," Giancarlo is beset by tarantulas and also dies. Francesco asks Rey to complete the film and Rey reveals that he already did so before he was fired. Francesco is ecstatic that his film is saved.
Father Clarke tries convincing Porfiry that Rey is not the killer. The priest mentions his belief that Porfiry is misguided by the superstition that in Roman times, editors were believed to be bridges to the netherworld.
When Cal learns that Rey edited him out of the movie, he threatens to kill Rey. Rey points out that Cal blinks whenever he tries acting, which is how he knows Cal is bluffing about killing him. Cal still vows to have his revenge.
Cal takes his suspicions about Rey to Porfiry. Porfiry mentions his belief that Rey may have ties to the occult and tells Cal that the best way to get to Rey would be through his wife.
Rey returns home to a ransacked living room. Cal then kidnaps Rey. Although Rey promises to put Cal back into "Tarantola," Cal forces Rey to watch as he has sex with Josephine. Josephine later reveals that she plans to leave Rey for Cal.
While researching the occult at the library, Porfiry is beset by tarantulas. Porfiry brings his findings to Father Clarke, who tells Porfiry about how Rey also patched the masonry in the church's bell tower. Meanwhile, the killer uses a chainsaw to murder Cal and Jasmine while they have sex.
After Ralphie discovers a severed hand while playing catch, Porfiry breaks into Rey's home and finds the occult book "Three Mothers" by Lilith Samael. Not knowing that the book is actually Josephine's, Porfiry takes it as confirmation of Rey's ties to the netherworld and goes in search of the man.
A chase between Porfiry and Rey ends with both of their cars going off a cliff. Rey flees the crash site and makes his way to Francesco's mansion, where Josephine is in the midst of sacrificing Francesco as part of an occult ritual. Porfiry chases Rey and shoots him. Josephine reveals herself to be an incarnation of Death. Porfiry attempts to shoot her, but blows off his own hand. Ultimately, Rey and Porfiry are able to kill Josephine. Porfiry reveals that Cal told him he was the person who killed Cesare, to get a better part in the film, although Josephine committed all of the other murders.
Porfiry returns to the police station and O'Connor tells him to see staff doctor Casini. Porfiry also learns that Josephine and Rey were never married and that Giancarlo is the chief inspector. Porfiry claims that Giancarlo should be dead. Confused, Porfiry runs to the church and learns from Father Clarke that Rey Ciso never patched the belfry and that the bell has not rung in over 100 years. Porfiry climbs the bell tower, digs through bricks, and discovers a skull on top of a pile of film cans. Porfiry screams as he realizes that he is now in a different reality.
