Star Treks original pilot, The Cage, was filmed in 1964 but never aired at the time. It was not until decades later that it was made available to the public. In this episode, the very first Star Trek story opens with Spock speaking the first line of dialogue, Check the circuit, as we see the bridge of the U.S.S. Enterprise for the first time. The Cage shows us a Spock who had not yet been fully formed by the writers of the show into the version we would come to know for most of Star Treks history. This Spock is still a sharp, efficient officer, full of scientific curiosity, but he displays emotion much more easily than in later appearances. He smiles sincerely when examining some plant life on a planets surface, his face aglow with childlike wonder and the joy of discovery. Later, when the Enterprises captain, Christopher Pike (played by Jeffrey Hunter) is in danger, Spock displays genuine concern for the safety of his commanding officer.