Annie has convinced the study group to become the Greendale Anti-Drug players and they'll be putting on a play for 50 middle-schoolers. The play couldn't have gone worse if they tried, and culminated with the kids chanting "we love drugs!"
The fault, of course, lies almost completely with Pierce. He bought Annie out by offering her a big fat check to help pay the rent. From there, his "additions" to the play grow further and further out of control. At intermission, the check-exchange is revealed and the group is sad to find that Annie has compromised her morals—and the play. With Pierce gone and an auditorium filled with youngsters chanting for drugs, things looked bleak—until Chang offered up his services.
Chang saves the day and in doing so, Shirley gets over her issues with him (how he might be the father of her unborn child, remember?) and finds the fact that he saved the day pretty endearing. Oh my—will Shirley give in to Chang's love? I sure don't know, but I'm excited to find out!