'Glee' Cast Previews 'Bittersweet,' 'Emotional' Graduation Episode

Glee Props/Nationals Group Stage - H 2012

Glee Props/Nationals Group Stage - H 2012

Glee's graduating class of 2012 ventures out into the unknown -- and potentially New York for some -- on Tuesday when New Directions changes forever as seniors Rachel (Lea Michele), Finn (Cory Monteith) and Kurt (Chris Colfer), among others, move on from McKinley High during the Season 3 finale.

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The episode promises to be a tearjerker as the seniors' departure impacts everyone as they begin to take the next step forward: letting go and moving on from the safety of high school and glee club. For some, the path is clear (Rachel is likely a shoo-in to go to NYADA after impressing Whoopi Goldberg's Carmen at Nationals), while for others it's less than crystallized (lookin' at you, Puckerman).

While all the cast will return for the dual-setting fourth season, with half the story set for the East Coast and the other at McKinley, it's unclear how big everyone's role in the upcoming season will be. One thing, however, is certain: Tuesday's Season 3 finale could likely serve as the last time the cast as we've come to know it performs as the original New Directions in the choir room. The Hollywood Reporter caught up with the cast at a TV Academy panel this month promoting the show for Emmy voters to get a sense of what filming the emotional hour was like.

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"I was caught by surprise by the emotion of some of the scenes I'm doing in the finale with the kids who are graduating," Jane Lynch (Sue) tells THR. "Sue is pregnant and I think her heart is open; she's more vulnerable than she's probably been in her life and she's about to give birth to this new life and it affects her with graduation and she transfers those feelings onto the kids."

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The episode also marks a big one for Naya Rivera's Santana, whose mother -- played by Grammy winner Gloria Estefan -- pops in to help her daughter weigh attending the University of Louisville on a cheerleading scholarship or following her dreams of becoming a star. "Filming the finale was at times very emotional because it felt like the culmination of the last three years of us working on the show and all of our personal memories," Rivera tells THR. "At the end, it was joyous and everybody was happy; it turned out well."

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For Rivera's on-screen girlfriend, Heather Morris (Brittany), the episode was the same as any other -- just with an added component. "It's more emotional because we don't really know about next year," she tells THR. "Other than that, it's the same with us because we're always together all the time. There's a lot of crying and everybody keeps saying it's so sad but then five minutes later everyone's saying, 'I'm tired, let's go home.' "

Monteith, whose Finn is poised to study acting as he plans to accompany Rachel to New York, says the episode was "bittersweet." "It's great that he gets to graduate but at the same time it's always hard," he tells THR. "In real life and on television, you see seniors leaving the school and leaving to the unknown in Season 4."

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Michele, meanwhile, noted that knowing what was ahead in Season 4 didn't help her contain her emotions while shooting the season finale. "I've already broken down once and it's going to happen again even though I know I'm coming back next year," she said.

What do you hope to see happen? Hit the comments with your thoughts. Glee's Season 3 finale airs Tuesday after American Idol at 9 p.m. Check out a promo for the episode below.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit