Adam Christie

Five university friends gather at a house party to ring in the New Year. Unbeknownst to them, an epidemic has erupted outside, causing outbreaks around the world.

A bike courier suffers a traumatic accident. As she recovers, she begins to experience strange episodic-black outs, hallucinations, and night terrors-that lead her to discover that she has a tumor, a benign growth that is the remnants of a "vanishing twin" absorbed in utero. Over time, the tumor manifests itself as the dark and demented version of a stranger. (imdb)