Glee Season 5 will welcome Finn Hudson back to the series.

Corey Monteith's rehab stint might have given him an important refresh. This is great news for Finchel fans. However, the Fox show will miss some of the series' original characters - perhaps for good. As inevitable as this change might be, many fans are disheartened to see their favourite characters exiting the dramedy. Quinn, Puck, Mercedes and Mike are not likely to make multiple appearances. Brittany is also not likely to return.

Heather Morris' Brittany takes a bow in Glee Season 4 finale, luckily with Naya Rivera's Santana in the episode for a proper closure for their fans. Morris, who is pregnant with her first child, has said in previous interviews she is looking forward to be a doting mum. Brittany and the rest of the original characters could still appear once or twice, but fans are not encouraged to keep their hopes up.

In an exclusive TV Line report, the other characters leaving the show have been revealed. Dianna Agron (Quinn) showed up for only 3 episodes in Glee Season 4. The last time fans saw her, she's exploring her sexuality with Santana. It was hoped she'd eventually move to New York. But having Santana move to NYC with Rachel and Kurt is more than a consolation. As for Agron, she will be seen in "The Family" with film co-stars Robert De Niro and Michelle Pfeiffer.

Mark Salling (Puck) was in multiple episodes last season. His character being linked to half-brother Jake is supposed to promise several recurring appearances. But the actor may have filled out his fall calendar this early. Amber Riley (Mercedes) and Harry Shum Jr. (Mike) are also moving on from Ryan Murphy's show choir.

In a related Gleek development, the new generation characters will have a sharper focus next season. The Hollywood Reporter announced Melissa Benoist (Marley), Jacob Artist (Jake), Becca Tobin (Kitty), Blake Jenner (Ryder) and Alex Newell (Unique) have all been promoted to series regulars.

Fox has earlier granted Glee two more seasons, allowing the show runners to better prepare for the ending of the series.

When Glee Season 5 kicks off in September, New Directions will be prepping for the seniors' graduation and their participation at the Nationals competition in L.A.

VIDEO: Jane Lynch Talks Glee Season 5

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