While Dwight settles for a job at Staples, Andy tests the last nerve of his coworkers, particularly Michael and new deskmate Jim, to whom he shows off his cell phone ringtone that he sang himself. Michael welcomes Oscar back to the office by asking the Party Planning Committee to throw a Mexican-themed fiesta.
Jim tries to enlist Karen's help in pulling a prank on Andy, but she is busy with Dwight's former clients. Pam, however, is a ready accomplice. With her help, Jim hides Andy's cell phone in the ceiling above Andy's desk.
Michael's rejection of Andy's friendship, combined with Pam and Jim's prank of continually calling his "lost" phone, pushes Andy over the edge, and he punches a hole in the wall in frustration. This—combined with learning from a depressed Angela that Dwight went to Corporate to deliver an important document—causes Michael to realize that he made a mistake in forcing Dwight to resign, and he goes to Staples to get him back.
At the party, Karen confronts Jim, asking him if he still has feelings for Pam. After several seconds of silence, Jim quietly answers, "Yes." Karen gets up and walks out, visibly upset.