When a US Government satellite crash-lands in Utah, a deadly bacteria is let loose. The repercussions are terrifying, as a plague is unleashed on a nearby town, and every single inhabitant is killed save for an old man and a baby. As the lethal plague starts to spread, and the military fights to contain it, a crack team of scientists led by epidemiologist Dr Jeremy Stone (Bratt) are isolated in an underground laboratory with the two survivors. In a desperate race against time they try to find a way to immunise people against the killer virus before it wipes out the planet's entire population.