The Thirteenth Floor (1999)

In late 1990s Los Angeles, Hannon Fuller (Armin Mueller-Stahl) owns a multi-billion-dollar computer enterprise, and is the inventor of a newly-completed virtual reality simulation of 1937 Los Angeles. When Fuller is murdered, just as he begins premature testing of the VR system, his friend and protégé, Douglas Hall , becomes the primary suspect, and begins to doubt his own innocence.

Between questionings by LAPD Detective Larry McBain , Hall meets Jane Fuller , who is the estranged daughter of the dead Hannon Fuller. Hall romances Jane, who is busy with the shut-down of the new VR system. When a local bartender (witness to a murder-night meeting between Hall and Fuller), is found murdered, Hall is imprisoned, but soon released, after Jane gives him an alibi.

Seeking answers, Hall attempts to track and find a message Fuller left in the simulation. In the VR system, Hall takes the form of a banker named John Ferguson, and even learns that bartender Jerry Ashton (Vincent D'Onofrio) has stumbled upon the truth about his artificial nature — he read the message Fuller addressed to Hall. Frightened and angry, Ashton tries to kill Hall, who barely survives to escape the virtual reality.

Now unable to find Jane, Hall discovers her double, Natasha Molinaro, working as a grocery store clerk — but Molinaro does not recognize Hall. This leads Hall to perform an experiment outside the VR system, something that Fuller’s letter instructed him to try: drive to a place where he never would have considered going otherwise. At a given point during the trip, he stops the car seeing how the area, and everything within it, are replaced with wireframe models. Finally understanding the meaning of inventor Fuller’s message, Hall grasps the truth: that 1990s Los Angeles — his world — is a simulation.

The facts: Douglas Hall's virtual world is one of thousands, but also is the only one that developed a virtual world of its own. Jane Fuller lives in the “real world” — and only participated in the 1990s simulation to assume the identity of Hannon Fuller’s daughter, gain control of the company, and shut down the simulated 1937 reality. Hall is modeled after David, Jane’s real-world husband, who, in the 1990s simulation, is seeking pleasure by murdering people. It was David who committed the murders (whilst controlling Hall’s body), on becoming jealous when his wife Jane fell in love with Hall, in the simulation.

Whitney (Vincent D’Onofrio), Hall's associate, enters the 1937 simulation, assuming the role of bartender Jerry Ashton, who has kidnapped Ferguson (Hall’s 1937 identity) and bound him in the trunk of his car. When Whitney is killed in a car crash, Ashton’s consciousness is released to Whitney’s body . Ashton kills a security guard, David assumes control of Hall, kills Ashton, and attempts to rape and murder Jane, who is saved by Det. McBain shooting and killing David.

That death releases Hall’s consciousness into David’s body; he wakes in 2024, connected to a VR system. He disconnects the system and finds Jane and her father, much resembling Hannon Fuller, the man he was accused of killing in his original reality. The film ends when Jane wants to tell Hall more about the simulation, but the film ends like a computer monitor being turned off.