Moebius (1996 film)

Plot

On March 4, the control room of the Buenos Aires Underground realizes that train UM-86, a Siemens-Schuckert Orenstein & Koppel model, has vanished inside the tunnel system, passengers and all. A thorough search of the entire network—depicted in the film as far more extensive than its real-life counterpart—turns up nothing. To keep the public in the dark, the SBASE director reaches out to the engineering company that built the line where the train disappeared, hoping for an investigation. Instead of sending a seasoned engineer, the firm dispatches a young topologist named Daniel Pratt, much to the director's frustration.

Pratt heads to a national archive to find the line's original blueprints, only to learn they have been removed by Hugo Mistein, a former lecturer of his at the University of Buenos Aires. At the university, another professor informs Pratt that Mistein retired long ago and hasn't been heard from since. Pratt manages to get Mistein's address and calls from a payphone. A young girl answers, unhelpfully states that Mistein is out, and hangs up. Out of coins, Pratt decides to visit the apartment in person.

The same girl opens the door, and after some hesitation, lets him inside. There, Pratt finds the missing plans, but a knock at the door forces him and the girl to flee via the fire escape. They make their way to a station to find the director. Pratt leaves the girl waiting on a platform while he meets with the director and a group of officials assembled to solve the UM-86 mystery. They tell him the entire line has been shut down and all trains stopped to aid the search. Just as this news is delivered, the sound of a train echoes through the tunnels.

The group dashes around the multi-level station, hunting for UM-86, but it is nowhere to be seen. Maintenance workers on the lowest level also heard the noise, but assumed it came from the upper level where Pratt and the others were. In response, the director orders all power to the line cut off, an action that does little beyond irritating the committee further.