At the end of September 2003 there was a mass infection of people with cordyceps all over the planet. Previously parasitized only on insects, the fungus had adapted to survive in the human body, completely subjugating the host's will and changing its appearance. On the very first day, Joel, a construction worker who found himself in the epicenter of the pandemic, suffered an irreparable loss.
20 years later Joel lives in the Boston quarantine zone, which is under strict control of the Federal Agency for Disaster Management, and together with his girlfriend Tess tries to get a car battery to go in search of his brother in another state. Fate brings him together with a wounded rebel leader who promises a car and a battery if Joel and Tess will deliver the wayward 14-year-old orphan Ellie to a squad of battle buddies waiting for her outside the quarantine zone.