World on a Wire (German: Welt am Draht), is a 1973 science fiction film directed by Rainer Werner Fassbinder. Shot in 16 mm, it was made for German television and originally aired in 1973, as a two-part miniseries. Starring Klaus Löwitsch, it was based on the novel Simulacron-3 by Daniel F. Galouye. An adaptation of the film was presented as the playWorld of Wires, directed by Jay Scheib, in 2012.
At the Institute for Cybernetics and Future Science ("Institut für Kybernetik und Zukunftsforschung, IKZ"), a new supercomputer hosts a simulation program that includes an artificial world with over 9,000 "identity units" who live as human beings, unaware that their world is just a simulacron. Professor Vollmer (Adrian Hoven), who is technical director of the program, is apparently on the verge of an incredible secret discovery. He becomes increasingly agitated and anti-social before dying in a mysterious accident. His successor, Dr. Fred Stiller, has a discussion with Günther Lause, the security adviser of the institute, when the latter suddenly disappears without trace, before passing on Vollmer's secret to Stiller. More mysterious still is the fact that none of the other IKZ employees seem to have any memory of Lause.
Meanwhile, one of the identity units in the simulation attempts suicide. This unit is deleted by Stiller's colleague Walfang, to keep the simulation stable. To investigate the reasons for the suicide, Stiller contacts the contact unit of the simulated world. The unit, called Einstein, is the only identity unit who knows about the simulation, and this is necessary to run the program. In an attempt to become a real person, Einstein switches his mind into Walfang's body while the latter is in contact with the simulated world. Einstein gives Stiller an explanation for the mysteries, vanishing memories, and vanishing persons. He tells him that the real world is nothing else but a simulation of a real world one level above.
This knowledge causes Stiller to slip into insanity. The other "real" people interrogate Stiller, and he is threatened with death, incarceration, and involuntary commitment. Stiller is finally able to convince Hahn, the IKZ psychologist, of his theory. The latter soon dies in an accident that is pinned on Stiller, marking him as the suspected murderer of both Hahn and Vollmer.
Stiller flees and searches for the necessary contact unit who can connect the "real" world with the real world a level above. He survives several assassination attempts and discovers the contact is Eva, Vollmer's daughter, with whom he had once had a romance. Eva tells him he was modeled on the real Fred Stiller, a person whom Eva loved, but became mad with power from directing the simulation in the world above. While Stiller is programmed to die in an ambush, Eva switches the minds of the two Stillers and brings the simulated Stiller into the real world.