The third season of the NBC superhero drama is divided into two distinct story arcs: Volume 3: Villains and Volume 4: Fugitives . Released in 2008–2009, this season consists of 25 episodes and explores the thin line between heroism and villainy through the introduction of a "formula" that can grant anyone superhuman abilities. Season Structure and Plot Heroes – Season 3, Episode 12 Review - geeky talk