Showtime has unleashed the sixth trailer for Dexter, returning for Season 7 with the premiere episode "Are You...?" Friday, September 30 at 9 PM ET. The world of Michael C. Hall's Dexter is starting to come unraveled, with his sister Deb (Jennifer Carpenter) beginning to realize who he really is. Take a look at this video with scenes from past episodes of this hit series that lead into the new season.