Behind the Scenes of the 'Glee' Season Finale

Although this isn't a final farewell, Glee's upcoming season finale has been an emotional rollercoaster for most of the main cast members.

VIDEO: Glee Cast Teases Emotional Season Finale

"We're all really enjoying every single moment of what we're doing because it's not going to be like this again," said Cory Monteith, who plays one of William McKinley High School's graduating members.

Jenna Ushkowitz added, "I know that we'll see the choir room again, but it's definitely going to be a different vibe, a different energy."

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Dianna Agron illustrated how the girls have been coping with the pending transition, saying, "We're using water-proof mascara during this episode," implying that a lot of tears have been shed over the course of shooting.

Watch the season finale, titled Goodbye, airing Tuesday, May 22 at 8/7c on FOX.