Glee fans can now see a sneak peek of the upcoming flashback episode set to comprise the first of the show's two-hour series finale.

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The first part of the two-hour finale of Glee is an episode called 2009 and features a flashback to this year, which was when Rachel (Lea Michele), Kurt (Chris Colfer), Mercedes (Amber Riley), Tina (Jenna Ushkowitz), Artie (Kevin McHale) and the late Finn (Cory Monteith) auditioned for the glee club.

Fox has now released a sneak peek of the episode, with McHale and Ushkowitz discussing the episode.

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"It is a flashback of what happened during the pilot that we didn't see," McHale explains. "It's kind of fun to get to see why everybody signed up for glee club, and to audition in the first place because in the pilot you just kind of jump into it."

Ushkowitz goes on to explain that "we're going to see how we all started. So for Tina, she had a stutter but now we know it was fake. So we're going back and talking about how it was her plan all along, her evil plan."

McHale adds, "We get to actually see what motivated all of us to actually audition and want to do it."

Ultimately, this episode is a special one "because it's just nostalgic, even for us," McHale says.

The characters are wearing all of their original costumes, with the actors having to perform their characters as they were back in the pilot episode. Since six years have now gone by, it should be fun to see how much the core characters have grown since the first episode.

Glee airs its two-hour series finale on Friday at 8 p.m. ET/PT on Fox.

Watch the sneak peek of the 2009 episode of Glee here: