Preview Clip of Grey's Anatomy Season 8, Episode 17: Why Is Catherine Avery Back? Tweet March 15, 2012 by Rebecca Martin Related: Grey's Anatomy, Miranda Bailey , Richard Webber , Season 8 Episode 17 Credit: ABC © 2012 Disney ABC Television Group Air date: March 15, 2012. Catherine Avery returns on Grey's Anatomy Season 8, Episode 17: "One Step Too Far."
