Ive known about this movie for so many years, she says.

So I always was joking throughout the years, There better be a part for me in there.

It started off as a little cameo.

ALL CROPS: EW COVER 1443 “Office Christmas Party”, Olivia Munn, TJ Miller, Courtney B. Vance, and Jennifer Aniston photographed exclusively for Entertainment Weekly by Eric Ray Davidson on November 3rd, 2016 in Los Angeles.

Credit: ERIC RAY DAVIDSON for EW

It was supposed to be just a small little thing.

Interjects Munn: And then they go, Wait, Jennifer Aniston is willing to be in the movie?

What if we call it a cameo and just extend it and extend it?

Day 15, she thought it was a cameo still.

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Meanwhile, Vance, the Emmy-winningPeople vs. O.J.

It was a switch that he would flip.

Adds Vance: As actors we all love challenges.

The stars insist, though, that theres more toOCPthan hedonistic showboating and unexpected blow.

Its more: The next day, all will be forgiven, so everybody goes for it that evening.

And that was the feeling, actually, on the set.