Season synopsis
Contains spoilers for this season and earlier seasons.
In the study group's third year, Chang returns to Greendale as a security guard after his Spanish-teaching credentials were exposed as fraudulent. He turns Dean Pelton's trust into an opportunity to seize the school, building a fake security force and trying to rule the campus. At the same time, Vice Dean Laybourne notices Troy's instinct for repairing air-conditioning equipment and recruits him into the secretive Air Conditioning Repair Annex. Troy is drawn to the prestige and discipline of the program, while Abed fears their close partnership will change. Pierce and Shirley also clash over a sandwich shop they have opened together, taking their dispute into court.
Chang's coup ends with the study group expelled from campus. They sneak back in, free the Dean and expose Chang's takeover to the school board, which removes him and reinstates them. Troy's Annex story reaches its own turning point after Laybourne dies: Troy challenges successor Murray, wins their repair contest, saves Murray and leaves the Annex to return to his friends. The Annex is incorporated into Greendale as an ordinary program, rather than keeping Troy as its leader. Jeff passes his biology final after defending Shirley in student court, where he refuses to sacrifice her interests to regain a job at his old law firm. These endings restore the group's place at school, but leave Troy to decide what he wants beyond the specialized role Laybourne had prepared for him.