This one-hour special marks the 20th anniversary of Sesame Street, the ground-breaking educational children's series that has taught numbers and the alphabet, along with social and cultural concepts, to generations of preschoolers. Hosted by Bill Cosby, the retrospective includes appearances by Muppet characters Big Bird, Grover, the Count, Kermit the Frog, and Bert and Ernie, as well as Sesame regulars Bob, Gordon, Susan, Maria, and Luis, and many others. Kermit the Frog and Jim Henson introduce the show.