Castle

Season 4, Episode 2

Episode Title: Heroes & Villains

Air Date: 2011-09-26

Overview:

When an ex-con is mysteriously slain in an alley, Castle and Beckett believe a vigilante is behind the murder. But efforts to identify their suspect are thwarted when they discover that he roams the city in a Superhero costume – and may indeed be a Superhero. Can they capture and unmask the killer before he strikes again?