FLASHBACK: Inside the 'Mary Tyler Moore Show' 2002 Reunion With Betty White and Valerie Harper

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Mary Tyler Moore's beloved 1970s sitcom, The Mary Tyler Moore Show, left an indelible mark on the TV landscape for its bold and progressive depiction of self-determined women and edgy comedy.

The show -- which ended up spinning off two other sitcoms, Rhoda and Phyllis, as well as the drama series Lou Grant -- came to an end in 1977. But Moore got a chance to reconnect with her former Mary Tyler Moore Show cohorts Valerie Harper, Betty White, Cloris Leachman and Georgia Engel in 2002 for a very special reunion, and ET was on set for an exciting look at the icon at work.

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For the long-awaited reunion, Moore -- who died on Wednesday at the age of 80 after going into cardiopulmonary arrest -- wanted to make sure that the special was satisfying and truly meaningful for longtime fans of her celebrated series.

"I wanted to have a sense of who the people who played those characters are," Moore told ET at the time.

The day ET came to the set, the energy was electric and it was clear that there was nothing but love between the actresses, who Moore said rarely got a chance to be around each other.

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"I live in New York and everyone else lives in L.A., so it's not like we run into each other at the local soda shop," she joked.

While Moore's relationship with Harper, Leachman and Engel remained strong over the years, perhaps her closest friend from the groundbreaking sitcom was White.

The two actresses had undeniable comedic chemistry on the show, and off-screen, also shared an unshakeable bond.

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"Betty is my old and dear friend," Moore shared. "I can't think of anyone I'm more comfortable with sitting around and chatting about anything with than her."

11 years later, all five of the close co-stars reunited once again, this time on the set of White's TV Land sitcom, Hot in Cleveland, for another special reunion that also ended up being Moore's final appearance on TV. Check out the video below for more.