Recording sessions. Choreography lessons. Concert tours. And that's not to mention the 121 hours of TV the stars of Gleehave logged over the past six years. After such a whirlwind run, it makes sense that it took the cast a beat to wrap their heads around saying goodbye.

"It's over, but holy crap did we seriously just do this? That's it?" Darren Criss told reporters about the emotions of filming the series finale. "It wasn't sad to me, it was just really beautiful. It was more of like a 'Guys, we did it!'"

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However, it wasn't an easy final lap to the finish line. "I really think that [co-creators Ryan Murphy, Brad Falchuk and Ian Brennan] and the rest of our writers had a difficult task in wrapping up everyone's story lines and making sure that everyone was happy and also making sure to honor Cory [Monteith] and do all that in one episode," Lea Michele said. "They really did a great job to make sure that the fans were happy and that they were respectful of everyone's story lines."

The series finale, airing Friday at 8/7c on Fox, will aim to honor both the past and the future. The first hour, appropriately titled "2009," will flash-back to what life was like for the OG members of the glee club - Rachel, Kurt, Mercedes, Tina, Artie and even Mr. Schue - right as New Directions was getting off the ground. The second hour, "Dreams Come True," will show what's next. "We see everybody in five years," Jane Lynch said. "Everybody goes off and does different things and yet they all have Lima, Ohio to come home to and this group and this family of people who will always love and support them, and that's kind of great to go through your life knowing that."

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Looking ahead, Lynch said it will be the show's heartfelt story lines that will be an important of the show's legacy. "I think Ryan Murphy is fearless and he didn't back away from any subject," Lynch said. "Anything that kids are afraid of that will make them different, he put a spotlight on it and basically told them it doesn't make you different. It just makes you who you are."

Over the years, Glee has covered sensitive topics such as homosexuality, bisexuality, transsexuality, depression, domestic violence, eating disorders, learning disabilities and many more. "I just hope because it touched so many lives that people see the importance in just loving one another," said Dot Marie Jones, whose character Shannon Beiste transitioned from a woman to a man in Season 6. "You just want to do something that means something and, not that the other roles that I've done over the last 24 years haven't meant something, but I think it's just touched so many demographics. I think everybody can identify with at least one person on our show if not several."

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When asked about Glee's footprint, Mark Salling pointed to a recent news story inspired by fan-favorite Becky Jackson (Lauren Potter), Sue's outspoken and hilarious sidekick who also has Down's Syndrome. "I was listening to talk radio, and they're doing a news story based on this local high school cheerleader with Down's Syndrome. She was being bullied, I believe, at a game by the opposing team, and her basketball team stopped right then and there and stood up to the bullies and refused to play until they stopped. Her name was Desiree," Salling recalled. "At the very end of the story they go, 'Desiree was inspired to become a cheerleader from the TV series Glee.' .... I think that sums up what Glee is about and that's what everyone should take from it: acceptance and doing things that you might not think you should do or could do, and having that extra confidence and also brushing the bullies off."

The show's millions of viewers and millions of albums sold, it seems, are just a nice bonus. "That's what makes Glee so special is that it hit the mark in so many different aspects," Michele said.

Glee's series finale airs Friday at 8/7c on Fox.

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