A security guard, trapped in a run-down inner-city medical clinic, is terrorized by supernatural forces which threaten to overtake her.

Students on summer break are exposed to a deadly virus that is spread rapidly through direct human contact. The infected become enslaved by the invading "swarm" intelligence and driven by an insatiable appetite to consume human flesh. Returning home, the students spread the infection to their fellow classmates and other unsuspecting townspeople.