Hiro (Masi Oka) and Claire (Hayden Pannetiere) change the course of the catalyst 16 years ago, while Nathan (Adrian Pasdar) experiments with it in the present.

Get down with the sickness and watch the bodies hit the floor as forensic pathology students turn murder into a game in “Pathology.” (Neither Drowning Pool or Disturbed have anything to do with this film, but the lyrics seem to fit!)

An unlikely pair, Sylar (Zachary Quinto) and H.R.G. (Jack Coleman) are sent to capture the villains who escaped from Level 5.