Star Trek: The Original Series/Behind the scenes/Series begins

Preparations for the first regular season started in early . The interior sets of the Enterprise were renovated, and new uniforms were introduced. The show's appearance became more vibrant and colorful. Additionally, the Enterprise model received another update. The entire production shifted from Desilu's Culver City studios to Paramount's main Gower Street studios, specifically Stage 9 and 10, and later to Paramount Stage 31 and 32 from 1967 onwards in Hollywood.
Kirk (Shatner) and Spock (Nimoy) remained the central figures of the series, with Grace Lee Whitney joining as Yeoman Janice Rand, taking over from Andrea Dromm's Yeoman Smith. Whitney had previously collaborated with Roddenberry on an unsold pilot called Police Story a year earlier. At that time, publicity photos for the new series were taken, featuring the trio and mostly utilizing props from the earlier pilots, including the notable phaser rifle. In these photos, Shatner and Nimoy donned their new uniforms, whereas Whitney was clad in the older pilot version.
Scott (Doohan) and Sulu (Takei) remained, with the latter transitioning from physicist to the ship's helmsman. The Enterprise main crew was completed with two additions: DeForest Kelley joined as the new chief medical officer, Leonard McCoy, a role secured due to Roddenberry's familiarity with his work on previous projects, including Police Story. Actress Nichelle Nichols was cast as the communications officer Uhura, who emerged as a symbol of the show's commitment to racial and gender diversity. Nichols was a last-minute casting, joining just weeks before filming commenced on the first regular episode.
Jerry Finnerman assumed the role of director of photography, as Fred Phillips, Matt Jefferies, and Rolland M. Brooks resumed their previous roles. The writer John D.F. Black joined as the second associate producer alongside Justman. Roddenberry and Black managed script and story development, while Justman oversaw the physical production elements.
The filming of the first regular episode, , commenced on . Eventually, Star Trek premiered on NBC with a Sneak Preview episode at 8:30 pm (EST) on . NBC selected (the fifth episode in production order) as the debut episode, primarily because it was considered a "traditional monster story" and contained more action.