"100" is a double episode of the American television comedy series 30 Rock, comprising the 20th and 21st episodes of the fifth season, and the 100th and 101st episodes overall of the series. It was written by Jack Burditt and the show's executive producers Robert Carlock and Tina Fey, who is also the series' creator, head writer, and star. The episode originally aired on the National Broadcasting Company (NBC) network in the United States on April 21, 2011. Commemorating the 100th episode of the series, this episode was one hour long and included a multitude of guest stars including Michael Keaton, Tom Hanks, Rachel Dratch, Will Forte, Brian Williams, among others.