'The Office' Series Finale: Stars Break Down During Emotional Farewell (Exclusive Video)

The Office Series Finale - H 2013
Chris Haston/NBC

Dunder Mifflin is closing its doors.

After nine seasons, the veteran NBC comedy will say goodbye for good with a one-hour retrospective followed by the supersized series finale Thursday. To gear up for The Office's swan song, John Krasinski produced a series of farewell videos for NBC featuring interviews with cast members and past stars who have dropped by.

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The Hollywood Reporter exclusively debuts one of those videos with Brian Baumgartner (Kevin), Angela Kinsey (Angela), Phyllis Smith (Phyllis), Catherine Tate (Nellie), Oscar Nunez (Oscar) and Kate Flannery (Meredith) recalling their experiences being cast on the show.

Though many were aware of the potential for The Office to hit based on who was leading the charge (Steve Carell) and the material, Kinsey said there was a clear momentum shift -- at least for her. "I remember when we did the Christmas episode, the very first one, that next week we were the No. 1 download on iTunes," she says. "That's when I remember everything changed."

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For Nunez, being a supporting player on a show that's lasted nearly a decade is a welcomed experience: "It's a great place to be; you're on a championship team." Recalling an on-set moment, Kinsey shared that once when she and Jenna Fischer (Pam) were attempting to do a Laverne & Shirley staple, Carell reminded them that after all is said and done, they would gain a lasting friendship.

But when the interview turned to final goodbyes for the cast members, many of them struggled to maintain their composure, with an emotional Kinsey and Smith breaking down.

Watch the farewell video below:

The Office airs its series finale at 9 p.m. Thursday on NBC.

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