"The Trouble with Tribbles" is the 44th episode of the American science fiction television series, Star Trek, the 15th episode of the second season. It was first broadcast in the United States on December 29, 1967, on NBC. The episode was the first professional work of writer David Gerrold, and went through a variety of drafts before it reached the screen. Because of an error in the size of typeface, an approved version needed to be reduced by twenty pages before filming. Nichelle Nichols remarked that she had "never seen a script go through so many changes—and stay so much the same". "The Trouble with Tribbles" was directed by Joseph Pevney, who was one of the most prolific directors of the series.