After the explosion at the Chernobyl nuclear power plant number 4, the USSR and all of Europe is faced with an even greater threat - a possible steam explosion that would eject even more radioactive material into the atmosphere over the entire continent. Firefighter Alexey volunteers for what seems like a suicide mission: manually drain the plant’s reservoir before the melting reactor collapses into it. Risking their lives in service to their country, Alexey and his colleagues must navigate the labyrinthine passages of the plant’s underground, facing danger at every turn from the facility’s quickly failing infrastructure. With time running out, and the fate of all of Europe hanging in the balance, this team of ordinary citizens turned heroes must use all their strength and bravery to save their nation from complete devastation.