A mysterious and unexplained phenomenon begins in Central Park, causing mass confusion and an increasing number of bizarre and violent incidents. People in the Northeast United States suddenly start committing suicide in large numbers for no apparent reason, leading to widespread panic and chaos. As the event escalates, it becomes clear that this is not an isolated incident, but a terrifying and deadly crisis that is spreading rapidly along the Eastern Seaboard. The government is at a loss, and the cause of the strange behavior is unknown, leading to speculation about terrorist attacks or some kind of airborne toxin.

In the midst of the panic, a high school science teacher and his wife, along with their friend and his daughter, decide to flee Philadelphia in the hopes of finding safety. They embark on a desperate journey to outrun the invisible threat, encountering unnerving signs of the epidemic along the way. As society crumbles around them, the group must confront their personal issues and relationships while struggling to understand and adapt to the horrifying new reality. Their survival depends on their ability to keep moving and to unravel the mystery of the terrifying event that is destroying the world as they know it.