Episode 5 is called ‘Fight or Flight’ and will air on the 22nd of October. This is the official description as released by NBC:
SEARCHING FOR A LOST HERO, ELLE (GUEST STAR KRISTEN BELL) MAKES A SHOCKING DEBUT IN IRELAND — In Ireland, a lost Hero attempts to move beyond the past, but discovers that a mysterious woman — Elle (guest star Kristen Bell) — is willing to kill to find him. Matt (Greg Grunberg) and an unexpected ally fly to Philadelphia to hunt down the “boogyman,” 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. David Anders, Noah Gray-Cabey, Hayden Panettiere, Adrian Pasdar, Zachary Quinto, Dania Ramirez, Milo Ventimiglia also star. Alan Blumenfeld, Katie Carr, Jimmy Jean-Louis, Carlon Jeffery, Nichelle Nichols, Dominic Keating, Holt McCallany, Eriko Tamura, and Stephen Tobolowsky guest star.
Show Cast: Milo Ventimiglia, Ali Larter, Hayden Panettiere, Greg Grunberg, Sendhil Ramamurthy, Masi Oka, Adrian Pasdar, Noah Gray-Cabey, Jack Coleman, James Kyson Lee, Dana Davis, Dania Ramirez, Zachary Quinto, Kristen Bell, David Anders.