Six years have gone by since the birth of Chucky and Tiffany's intriguing offspring, a living doll who embodies both gender ambiguity and a surprisingly kind nature. This innocent being, known as “Shitface” and kept prisoner by the sadistic British ventriloquist known as Psychs, finds himself exploited for his unsettling charm on stage. Despite his seemingly gentle exterior, Shitface is haunted by nightmares filled with brutal violence, hinting at the darker aspects of his nature.
His mundane existence is transformed dramatically when he comes across a trailer for a film featuring Jennifer Tilly titled "Chucky Goes Psycho." This film showcases the revival of Chucky and Tiffany from their original forms. In a moment of clarity, Shitface seizes the chance to escape his captor and tracks down the resurrected dolls to a prop room in Hollywood. Armed with the mystical Heart of Damballa, a voodoo amulet inherited through his lineage, he manages to breathe life back into Chucky and Tiffany.
As their child, now referred to as "Glen" by Chucky and "Glenda" by Tiffany, approaches its parents with uncertainty regarding its gender—an intriguing consequence of being born without genitalia—the couple faces a profound dilemma about their child's identity. Amidst their own struggles, the trio embarks on a gruesome killing spree, targeting a special effects technician. In the shocking aftermath, Jennifer Tilly, the film’s protagonist, stumbles upon the heinous scene, leading her to alert the police immediately.
As Glen/Glenda observes the chaos unfolding around them, an innocent yet perplexing question arises: "Why do you kill?" Tiffany, overwhelmed by maternal instincts, urges Chucky to refrain from violence for the sake of their child, but he merely offers a disingenuous promise of compliance. Meanwhile, Jennifer Tilly is set on landing the role of the Virgin Mary in rapper Redman's directorial debut, attempting to charm him while her assistant, Joan, disapproves of her tactics.
As tensions rise, Chucky and Tiffany devise a sinister plan to transfer their souls into Redman and Jennifer. Tiffany takes drastic measures, rendering them both unconscious with the intention of using Jennifer as a vessel for Glen/Glenda's soul. In a surprise twist, Chucky whisks Glen/Glenda away on a reckless adventure, leading to the accidental death of paparazzo Pete Peters, who was relentlessly pursuing Jennifer Tilly. Afterward, Glen/Glenda is consumed by horror at this new reality, while Chucky finds joy in the mayhem.
Upon waking, Jennifer is struck by an unnerving realization—she believes she is with child, but Redman quickly clarifies that he has undergone a vasectomy. Adding to her fury, Redman dismisses her from his film, calling pregnant women unattractive. Infuriated, Tiffany seeks vengeance on Redman, witnessed by a conflicted Glen/Glenda who grapples with their duality. The following morning, Jennifer awakens to a mysterious bulge in her dress, the result of voodoo magic at play.
As the narrative unfolds, Chucky takes charge, kidnapping Jennifer and her loyal chauffeur, Stan. In a desperate bid to save Jennifer, Joan sacrifices herself to Glenda's wrath. The story reveals that Glen and Glenda are two distinct personalities merging within one body—one is gentle, while the other is a ruthless killer.
As labor pains hit Jennifer, she successfully gives birth to twins, a boy and a girl, only to discover that Tiffany has unlocked the shared soul of Glen and Glenda. However, Chucky undergoes a startling transformation, embracing his existence as a living doll and rejecting any remaining desire for human life. Tiffany's refusal to acknowledge his choice triggers a violent reaction, prompting Chucky to throw a knife at Jennifer in desperation. Stan, loyal to a fault, leaps in to save her, sacrificing his life in the process.
The police soon arrive, pressuring the dolls to flee, abandoning their sinister plots. Jennifer is rushed to the hospital, where Tiffany seizes the moment to control her body, but Chucky's sudden intervention takes Tiffany out of the picture for good. In a moment of vengeance, Glen strikes down his murderous counterpart with an axe, asserting his new will over his twisted legacy.
As the bloodshed concludes, Glen is left with the weight of his choices, confronting the devastation left in the aftermath. Jennifer Tilly comforts him, ushering in a new chapter filled with sorrow over his lost duality. Five years later, Jennifer Tilly is now focused on raising her two children, whose souls carry the essence of Glen and Glenda. The tranquility of a birthday celebration is shattered when a frightened nanny flees in terror, running away from Glenda's malevolence. In a fit of rage, Jennifer lashes out at the quaking nanny, only to reveal that Tiffany has successfully transferred her essence into Jennifer's body.
A shocking surprise awaits when Glen unwraps a birthday present to find Chucky’s severed arm, which inexplicably springs to life and ensnares him in its grasp.
