Beginning where the previous film left off, Mark Loftmore and Sarah Brightman flee the burning waxwork. They hop into a taxi, but a severed hand from the zombie exhibit escapes and shadows Sarah to her home, where it kills her stepfather with a hammer. Soon after, she stands trial for murder, and, to the dismay of her defense attorney, she recounts the night’s events at the waxwork to a skeptical jury. Mark, anxious to help, tries to corroborate her story from the spectators’ gallery, but he is abruptly removed from the courthouse.
Desperate to salvage their case, they visit the late Sir Wilfred’s home, where they discover a film reel in which Sir Wilfred speaks of his and Mark’s grandfather’s adventures and the supernatural artifacts they gathered together. A hidden switch in Sir Wilfred’s chessboard opens a door to a room full of objects, where Mark and Sarah find Solomon’s Locket, a device used by light and dark angels to travel through another universe, called Kartagra. Sir Wilfred explains that Kartagra is a multiverse where the eternal battles between good and evil unfold. Each victory or disaster in that cosmos is reflected back into their world, shaping peace or disaster here. Most of these worlds are grounded in fiction that has become reality, including Frankenstein, The Haunting, Alien, Godzilla, Nosferatu, and Dawn of the Dead, among others. Much like the waxwork exhibits, whenever Mark and Sarah arrive in a new world they assume the personas of characters from those stories, sometimes having their personalities taken over by those roles until they regain their senses. Those who stay in Kartagra to fight for or against evil are called time warriors.
Mark plans to gather evidence of the reanimated dead to bring back to their world as proof of Sarah’s story in court. After bouncing between worlds with little progress, they arrive in a medieval realm where Sarah is the sister of the evil sorcerer, Scarabis. Scarabis plots to seize the English throne by transmogrifying into the visiting king, leading to a tense sword duel between him and Mark. When Solomon’s Locket is opened, the pair continue leaping through various worlds. In a mall world ravaged by a zombie invasion, Mark slices off a zombie’s still-animate hand and keeps it as evidence for Sarah’s trial. They eventually wind up back at Scarabis’s castle, where Mark gains the upper hand and Scarabis dies at the hands of a woman who was transformed into a grisly panther creature during a ritual to grant him power. Panther Girl emerges as the vengeful force behind the sorcerer’s downfall.
When Mark and Sarah attempt to return to their universe, the doorway adapts once more, this time allowing only one of them to enter. Mark reasons that Sarah should go through and clear her name, even though she’d prefer to stay with him. Though resistant, she steps through, and Mark bids her a tearful farewell. Sarah returns to Sir Wilfred’s secret vault with the zombie hand in tow. She discovers a partially covered painting she had seen earlier, which turns out to be of Mark, dressed as an armored time warrior.
At the trial’s conclusion, Sarah’s steadfast evidence and resolve prove her innocence. As she exits the courthouse, a courier delivers an antiquated package containing Solomon’s Locket and a parchment from Mark that reads:
> Join me
Sarah boards a taxi, and the crowd outside watches as she disappears in a flash of light, leaving the world to wonder if the bridge between Kartagra and reality has finally accepted her call.
