S6, E9: Because he already considers himself an experienced con man, Jeff refuses to enroll in Greendale’s Basic Grifting class and advises his friends against it, too. Dismissing his warning as jealousy, Annie, Frankie, Abed, Elroy, Chang, and Britta sign up for Professor Roger DeSalvo’s Grifting 101. But when they are each conned into spending $150 on a regulation “grifting briefcase,” the group concludes Jeff was right and asks him to help get revenge.