Every Star Trek fan knows the name D.C. Fontana — the pen name of writer and producer Dorothy Fontana. Sadly, according to the AFI — where Fontana has worked as a senior lecturer — Fontana “passed away peacefully last evening at the age of 80.” The cause of death was listed as a “brief illness.”

The obituary provided by AFI gives a good overview of why Fontana is revered among Star Trek and sci-fi fans for her pioneering work in television:

Fontana gained global notoriety for her writing and story editing on the 1960s television series Star Trek, as well as the 1970s animated series, which she also associate produced. Her myth-building work on classic Trek blazed a trail for women, not only in television, but also in science fiction. Her well-known screen credit kept the fact of her gender a secret from most fans until they saw her picture in Stephen Whitfield’s The Making of Star Trek, one of the ‘bibles’ of classic Trekker fandom.

Fontana, who was born in New Jersey in 1939, was already working in television by the time she came to Star Trek. Her first produced Trek script was the show’s second episode, “Charlie X.” Initially employed as Gene Rodenberry’s secretary, she was soon promoted to story editor during Star Trek’s first season. Her writing credits on the series include “Tomorrow Is Yesterday,” “Friday’s Child,” and one of my personal favorites, “Journey to Babel”:

After the end of the original Trek, Fontana became a writer and producer on the Star Trek animated series. She penned perhaps the show’s best episode, “Yesteryear,” which revealed previously unexplored details about Mr. Spock’s childhood. Although the animated Star Trek is mostly considered outside of continuity, Fontana’s Spock backstory has remained a key part of the character’s official history.

Fontana later worked on the first season of Star Trek: The Next Generation, where she co-wrote the pilot episode, “Encounter at Farpoint,” with Gene Roddenberry. Although she left the show fairly early into its run, she later contributed a script to Star Trek: Deep Space Nine as well.

Outside of Star Trek, Fontana worked on shows like BonanzaThe Six Million Dollar ManLand of the LostKung Fu, and Babylon Five. In later years she also wrote Star Trek comics and a novel, Vulcan’s Glory, exploring more of Spock’s history. In short, her contributions to Star Trek, television, and science fiction are enormous — all the more so given the times in which she was working, which were often less than hospitable to women writers and producers. She will be missed, but she has left an incredible legacy.

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