On a quiet family night in Chicago, Jason Dessen cooks dinner with his wife, Daniela, and their teenage son, Charlie, before stepping out for a quick visit with his former roommate, the now-famous neuroscientist Ryan Holder. Walking home, he is abducted by a masked man who knows intimate details of his life and forces him to an abandoned power plant. There, after intimidation and injections, the captor questions Jason’s life choices—particularly his decision to abandon elite research for family—and promises an unbelievable future before drugging himself. Jason loses consciousness under a swirl of strange visual phenomena.

He awakens in a quarantined facility where staff in hazmat gear celebrate his return after fourteen months. Leighton Vance, the facility head, fast-tracks him through decontamination and into a debrief led by Amanda Lucas. They insist Jason is the only pilot to have returned from a dangerous mission. Terrified he isn’t the person they think, Jason engineers a desperate escape through a bathroom window, flees to the lakefront, and hires a cab home.

Jason finds his brownstone transformed—luxurious, impersonal, and devoid of Daniela or Charlie. A trophy case displays the Pavia Prize for groundbreaking quantum work he never pursued in his memory. As Leighton’s team breaches the house, Jason dives down a laundry chute and escapes to an ER, where doctors find ketamine and an unknown psychoactive in his system. Public records now depict him as a vanished star physicist at Velocity Laboratories. He slips out before an involuntary hold can be placed.

Determined to find Daniela, Jason tracks down a successful artist version of her at a gallery opening. She recognizes him from a goodbye a year and a half earlier; this Daniela never knew a son named Charlie. Ryan Holder, now her partner and a university neuroscientist, alludes to building a compound for Jason’s secret work at Velocity. That night, Daniela cares for a feverish Jason and, moved by their connection, sleeps with him. At dawn, an armed intruder breaks in, murders Daniela with a silenced shot, and incapacitates Jason—proof that powerful forces are hunting him.

Jason awakes imprisoned at Velocity. Leighton admits sending the killer after Daniela as collateral damage in protecting their project. He shows Jason a vast humming cube in a hangar—the box Jason supposedly built—and footage of Jason entering it fourteen months ago and reappearing three days earlier. Later, Leighton parades a brutalized Ryan to coerce cooperation; Ryan privately confirms he created a drug that temporarily disables the brain’s observer effect, enabling human-scale quantum superposition in tandem with the box. After Ryan is taken away and killed, Amanda rebels, frees Jason, and together they lock themselves in the box, inject the compound, and commit to the unknown as security pounds on the door.

Inside, they find a surreal corridor lined with doors—a mental architecture of possible worlds. Opening doors deposits them into adjacent realities: an ash-choked ruin, the Velocity hangar in a world where an alternate Amanda is shot, and a lethal blizzard city that nearly kills them before Jason digs the buried box from the snow using a compass. Jason hypothesizes that their emotional states steer the corridor: fear opens to hostile worlds; focused intention yields specificity. He suspects Amanda’s Jason orchestrated his abduction to swap lives. They ration their remaining ampoules and resolve to navigate with discipline.

In alternating glimpses from Daniela’s perspective in Jason’s original world, her Jason seems subtly different—new habits, intellectual intensity, and romantic zeal—signals that an impostor has taken Jason’s place. Meanwhile, Jason and Amanda test written intent and land in a dazzling advanced Chicago, confirming precision matters. But when Jason writes “I want to go home,” they arrive at the power plant in a pandemic-ravaged Chicago. At his brownstone, a dying Daniela tells him their son has already succumbed. Jason grants her a morphine-assisted death and escapes a military pursuit back into the box, devastated. In a quiet forest world, Amanda helps him see how fear—rooted in losing his mother to illness—likely steered them there. He begins painstakingly listing the details of his true home.

Exhaustion and grief mount. In near-familiar worlds, Jason stalks versions of Daniela and even phones a pregnant Daniela belonging to another Jason. Amanda confronts him about the unsustainable spiral and dwindling ampoules. Eventually she leaves, urging him to choose through feeling rather than facts. Mugged and nearly destitute, Jason resists replacing a counterpart in a near-home world. With a final ampoule, he writes the story of meeting Daniela—the love that defined his choice—and opens a door guided by that intention.

Jason returns to his true Chicago and confirms it through countless intimate markers. Seeing the impostor—Jason2—with Daniela, he considers murder but discovers a chilling reality: many alternate Jasons have also arrived, coordinating in shadowy chats, some armed and already killing. Ambushed by doubles, he escapes by embracing unpredictability, then engineers an arrest for a public nuisance, forcing a controlled reunion with Daniela at the police station. He proves an impostor is at his college by having her call “Jason” during office hours; the man answers, confirming the deception. They retrieve Charlie and, on a public bench, Jason explains the multiverse, the box, Amanda, and Jason2—another version who chose career over family and then stole Jason’s life.

The family goes off-grid to a shuttered Wisconsin cabin. Jason floats a “lottery” among the Jasons to choose one claimant, planning to destroy the box, but Daniela rejects being a prize and fears a monster could win. Their fragile respite shatters when multiple Jasons track them. A brutal fight erupts inside the cabin. A slashed-face Jason attacks; Jason2 intervenes, kills the intruder, then turns his gun on Jason, justifying his theft as the pursuit of a regret-free life. With Daniela and Charlie present, Jason seizes a moment, disarms Jason2, and fatally stabs him. Dying, Jason2 returns Jason’s wedding ring and hints at a leather bag in the Suburban’s glove box. Under gunfire from other Jasons, the family flees into the woods and escapes by car. The bag holds the means to try something else—their way out.

Resolved to end the hunt, Jason, Daniela, and Charlie return to the South Side facility. Dozens of Jasons have gathered early for the proposed lottery. Daniela steps forward and claims their agency, condemning the violence, and another Jason concedes that her and Charlie’s choice matters most. The crowd parts. Inside the box, Jason doses Charlie, himself, and Daniela with Ryan’s drug. They enter the corridor together. To prevent pursuit by other Jasons who think like Jason, they let Charlie choose the door—anchoring their path to his untainted intention. He opens a door spilling light, wet earth, and the scent of unknown flowers. Hand in hand, the family steps toward a new world, choosing one another above every other possible life.