Season 4 began in fall 2019, showrunner Mike Schur said of the build-up to the finale,"the experiment that the original cast is sort of engaging and with these new people is really the first half of the season. It's [episode] one through seven. And then everything after that is the second half of the season, which is the results of the experiment and the sort of endgame that arises from those results.
Asked how early into the process he knew how the show was going to end, the showrunner said:"Somewhere in the middle of or at the end of season two, we sort of started imagining the ending. And in general terms, we stuck to the plan. "But the joy of having a writers room is that you get to leave your options open as long as you want and hope that someone in the room comes up with better ideas than the ones that you had. So it changed and morphed in sort of two different little winding paths, but the true endgame is generally speaking what I imagined it would be for a while.
"We tried to keep our options open as long as we could, and then once we really knew what the shape of it was we committed, and we knew what that whole thing was before we really started writing the last season."
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