Glee Season 5 will feature four fewer regular cast members.
TV Line has confirmed that Heather Morris, Mark Salling, Amber Riley and Harry Shum, Jr. - Brittany, Puck, Mercedes and Mike, respectively - have all been dropped from the series as regulars. Any or all may still show up for a guest spot, but their exact roles in 2013-2014 are unknown at this time.
Moreover, Dianna Agron is unlikely to return in any capacity on Season 5.
Fox announced its lineup of premiere dates this week, with Glee Season 5 slated to look very different and kick off on Thursday, September 19.