Mister Rogers plays a game in which a number of assorted items must be fit into an appropriate case. Betty Aberlin tells Mister Rogers that Mabel Mercer will be visiting. In the Neighborhood of Make-Believe, King Friday and Queen Sara ask Handyman Negri to play on his guitar while they wait for Mabel Mercer to arrive with Lady Aberlin. Dr. Bill Platypus begins to play a selection on the bagpipes. The king tells him he must stop. Mabel Mercer has given Lady Aberlin a costume changer. When the two pieces are fit together, her costume will change. After Miss Mercer arrives, she sings alone and then invites the assembly to sing with her. The King declares it “Mabel Mercer Day.”