Senior engineers of Zaslon JSC are sent to investigate multiple violations at a large hydrogen production complex in the center of the Technocity metropolis. In addition to identifying, they also need to adjust the system and eliminate problems on site. Arriving at the scene, the engineers become witnesses and victims of a major accident. The complex is blocked and leaves them and the rest of the workers in captivity. A series of breakdowns begins, which threatens all residents of Technocity. How to find the cause of all troubles when the whole complex is trying to stop you?