"Goodbye Mr. Fish" or sometimes "Good-bye Mr. Fish", "Goodbye, Mr. Fish" or just "Mr. Fish" is the second episode of the first season of the American sitcom The Cosby Show. The episode was directed by Jay Sandrich and written by Earl Pomerantz. "Goodbye Mr. Fish" originally aired in the United States on NBC on Thursday September 27, 1984, at 8:00 PM Eastern time.The episode focuses on the death of Rudy's pet goldfish, which was difficult to explain to her and difficult for her to deal with.