The world has been overrun by a lethal infection. Humanity ravaged by a pathogen that leaves victims demented, mutated, locked half-way between life and death. Major cities have been bombed. Manhattan has been reduced to radioactive rubble.
A rescue squad enters the subway tunnels beneath New York. The squad are searching for Dr Conrad Ekks, head of a research team charged with synthesising an antidote to the lethal virus. Ekks and his team took refuge in Fenwick Street, an abandoned subway station, hours before a tactical nuclear weapon levelled Manhattan.
The squad battle floodwaters and lethal radiation as they search the tunnels for Ekks and his team. They confront infected, irradiated survivors as they struggle to locate a cure to the disease that threatens to extinguish the human race.