Star Trek: The Original Series/Behind the scenes/Pilots/Second

For the second pilot, NBC once again requested three story outlines. These included by Samuel A. Peeples, as well as and by Roddenberry. Despite being the most costly option, NBC selected for its abundant action and impressive space spectacle. Nevertheless, the other two concepts were eventually developed into episodes for the series.
The second pilot's filming commenced in and was completed in nine days. All original cast members from were replaced, with the exception of Spock. Jeffrey Hunter, initially cast as Captain Pike, declined to return, largely due to his wife's belief that science fiction would damage his career. Roddenberry had considered Lloyd Bridges and Jack Lord for the new captain's role, but both turned it down. Ultimately, William Shatner, with his science fiction background from The Twilight Zone and The Outer Limits, was cast. He portrayed the captain, initially named James R. Kirk, later changed to James T. Kirk.
For the role of chief medical officer, Roddenberry selected the experienced actor Paul Fix. The part of chief engineer Scott went to Canadian actor James Doohan, while the young Japanese-American George Takei played the ship's physicist Sulu. Both Doohan and Takei continued their roles in the subsequent series, with Sulu serving as the helmsman. Lloyd Haynes was considered for the regular role of communications officer Alden, and Andrea Dromm for Yeoman , but neither actor was retained after the pilot.
Numerous production staff underwent changes. Robert Dawn was the head make-up artist, while Fred Phillips resumed his role in the series. Academy Award-winning cinematographer Ernest Haller emerged from semi-retirement to become the director of photography. Associate producer Byron Haskin was succeeded by Robert H. Justman, who took on the combined roles of producer and assistant director.
The Enterprise model received updates for the second pilot, including numerous new outer space effect shots, many of which were later reused in the series. The sets underwent slight revisions, particularly the main bridge and the transporter room. While most uniforms, props, and sets were carried over from , some new props, such as the one-time-only phaser rifle, and a fresh matte painting of the planet Delta Vega, were created specifically for this episode.
 was approved by NBC, leading to the commissioning of the first season of a regular series for the 1966-67 television season. It was a historic moment.