the episode mentioned in the beginning was written by?
David Gerrold
The Trouble with Tribbles
The Trouble with Tribbles" is the fifteenth episode of the of the American science fiction television series "". Written by David Gerrold and directed by Joseph Pevney, it was first broadcast on December 29, 1967. In this comic episode, the starship "Enterprise" visits a space station that soon becomes overwhelmed by rapidly-reproducing small furry creatures called "tribbles". 

who was almost cast in star trek tos UNANSWERABLE the trouble with tribbles is it a film or series? It is the  fifteenth episode of the of the American science fiction television series "". fifteenth episode of which series? "Star Trek" episode who created this series? Gene Roddenberry. who is the aforementioned person? An American television screenwriter, producer and creator which production company produced the previously mentioned series? Desilu Productions
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The Trouble with Tribbles [SEP] Introduction
"The Trouble with Tribbles" is the fifteenth episode of the of the American science fiction television series "". Written by David Gerrold and directed by Joseph Pevney, it was first broadcast on December 29, 1967. In this comic episode, the starship "Enterprise" visits a space station that soon becomes overwhelmed by rapidly-reproducing small furry creatures called "tribbles". It is claimed the short story "Pigs Is Pigs" by Ellis Parker Butler inspired the episode, but strong similarities to sections of the novel "The Rolling Stones" led the producers to seek a waiver from author Robert A. Heinlein. The original episode has had several produced follow-ups.