On an episode of Heroes entitled "Fight Or Flight," Peter (Milo Ventimiglia) attempts to move beyond the past, but discovers that a mysterious woman -- Elle (Kristen Bell) -- is willing to kill to find him. Matt (Greg Grunberg) and an unexpected ally fly to Philadelphia to hunt down the “nightmare man,” following his terrible attack on Molly (guest star Adair Tishler), but the pair finds themselves outmatched. Monica (Dana Davis) tries to come to terms with her new abilities and her role as a local hero. Suresh (Sendhil Ramamurthy) meets his new partner and gets a disturbing assignment. H.R.G. (Jack Coleman) takes a step to further protect his family. Meanwhile, as Hiro (Masi Oka) continues to fix the past in feudal Japan, Ando (James Kyson Lee) attempts to piece together historically what’s happened to his best friend.