Mister Rogers plays with a King Friday marionette. Mrs. McFeely shows Mister Rogers books about mushrooms and talks about the library.In the Neighborhood of Make-Believe, King Friday has Bob Brown fool Lady Aberlin by convincing her that the King Friday marionette is really King Friday and that the king can fly. Lady Aberlin tells Mr. McFeely and Lady Elaine. Although Lady Elaine is skeptical, they all rush to the castle to see. Lady Elaine notices the strings and exposes the king’s joke. When Mr. McFeely goes back to the museum to mow the grass, he finds a huge mushroom which Lady Elaine puts in her mushroom room. Mister Rogers explains that her mushrooms are poisonous. He has the viewers watch his big stop light and distinguish which light is on top, bottom, or middle. Mr. McFeely delivers a bunch of mushrooms to Mister Rogers.