NBC viewers were introduced to an innovative new television show called Star Trek on September 8, 1966—exactly 45 years ago today. The original groundbreaking series ran for only three years, but it left a lasting mark both on television and the science fiction genre.

After the cancellation of the original series, Star Trek continued with 11 feature-length movies, four additional live-action television shows, an animated series, and numerous adaptations to other media—ranging from video games to a major Las Vegas attraction. In this retrospective, we will take a look back at Star Trek's bold beginnings and powerful legacy.

Space Seed

Star Trek was created by television writer Gene Roddenberry. He reportedly began crafting the concept for Star Trek as early as 1961, but the idea didn't sail out of drydock until 1964 when he proposed the series to Desilu Studios. Roddenberry's original vision for Star Trek is preserved in a first draft of the pitch, which is dated March 11, 1964. Although some key elements of Star Trek appear in that early document, the show it describes is quite different from the Star Trek that fans know and love.

Roddenberry intended to model Star Trek after the 1957 show Wagon Train, bringing the successful formula of the popular Western television series into a science fiction setting. The cornerstone of the original Star Trek proposal was the idea that the characters would visit "parallel worlds" with similar culture to our own, but with differences "ranging from the subtle to the boldly dramatic."

The pragmatic Roddenberry thought that the familiarity of earth-like parallel worlds would make it easier for viewers to relate to the events and situations depicted in the show. It would also simplify production because it would allow allow conventional locations and props to be used in the series.

The "parallel worlds" idea (which seems slightly similar to the premise of the 1995 show Sliders) didn't really stick when Star Trek entered production. Although a number of earth-like planets—including some with histories that parallel earth's—appeared throughout the show, the settings were more varied than Roddenberry had originally anticipated.

Who am I to argue with history?

That wasn't the only major change between concept and production. According to the early draft, the show would feature the starship S.S. Yorktown, captained by Robert M. April. The main characters were to include an unemotional female first officer called only "Number One," a half-Martian lieutenant named Mr. Spook (yes, an extra "o") with "satanic" red skin and pointed ears, a cynical old doctor named Phillip "Bones" Boyce, and a South American navigator named José Ortegas.

The original unaired Star Trek pilot, which was called The Cage, was sort of a stepping stone between the original concept and the actual Star Trek series. The pilot features the starship USS Enterprise, piloted by captain Christopher Pike. Number One appeared in the episode, played by Roddenberry's then-girlfriend (and future wife) Majel Barret. Leonard Nimoy played Mr. Spock, but with a human-like personality.

The pilot had fairly slow pacing and an introspective flavor. It tackled the existential implications of illusion and delved into the troubled Pike's struggle with the isolation of command. The pilot was rejected by NBC because the station thought it was too heavy for a mainstream television audience. Despite this setback, the show was still destined to move forward. NBC requested a second pilot with a number of changes and were eventually satisfied.

Pike became Kirk, played by William Shatner. The character of Number One was dropped (though the nickname would later be used in the The Next Generation), Mr. Spock became the emotionless first officer, and Barret was recast in the role of Nurse Chapel (she would later play the voice of the computer and Lwaxana Troi on subsequent series). A considerable amount of footage from the first pilot would later be used in a two-part Star Trek episode called "The Menagarie," which won a Hugo Award for Best Dramatic Presentation.

Star Trek was culturally significant and broke new ground in several different ways. The show featured an ethnically diverse cast and the very first inter-racial kiss (Kirk and Uhura) ever shown on television. Its depiction of an idealized future for humanity, without poverty or conflict, was bold.

Despite the progressive characteristics, the show was still quite shallow in some ways. Roddenberry advised writers to avoid discussing or visiting Earth in their scripts because "television today simply will not let us get into details of Earth's politics of Star Trek's century; for example, which socio-economic system ultimately worked out best." Writers were instructed to extrapolate an optimistic future while avoiding specificity in areas that would make people uncomfortable.

Another area where the progressive tone and culture of the show falls short is in its treatment of alien species. The original series is relentlessly ethnocentric—it often depicts alien cultures as deficient and in need of human influence (in the form of mainstream 1960s American values, no less) to set them on the right track. It wasn't until the later series that Star Trek gained deeper anthropological substance and a more balanced view of humanity's cultural strengths and weaknesses relative to other alien species.

Fated to die of suffocation in the icy cold of space?

Although Star Trek was initially successful after the airing of the first episode in 1966, the positive ratings didn't last. The show had a loyal following, but its popularity was not broad enough to win NBC's continued support.

NBC was going to cancel the show after its second season, but reluctantly agreed to renew it for a third season after receiving a significant number of letters from fans. One of the chief organizers of the letter-writing campaign was Star Trek enthusiast Betty Jo Trimble, who would later be granted a minor role in the first Star Trek film in honor of her commitment to the show.

At the start of the third season, NBC decided to air Star Trek on Friday nights—a highly undesirable time slot that is typically used for sagging shows because it is notoriously bad for ratings and viewership. There was little hope that Star Trek would survive for a fourth season. Although a second letter-writing campaign was launched, NBC canceled the show.

With only three seasons, the original show is the shortest of the live-action Star Trek series. It continued to gain popularity after the cancellation, however, when reruns started to play after its cancellation in 1969. It remained enormously popular in syndication for two decades after it was canceled.