Lieutenant Osborne was a male Human Starfleet officer who lived during the mid-23rd century. He served in the operations division aboard the USS Enterprise under Captain James T. Kirk, during Kirk's historic five-year mission.
In 2267, he served in the command division, serving as one of the ship's navigators. On stardate 3158, was the navigator when Sulu returned to duty after recovering from the power of Landru (TOS: "The Return of the Archons")
Later that same year, he transferred to the operations division, where he became a security officer. On stardate 3192, he accompanied Captain Kirk in a landing party that visited Eminiar VII. Briefly imprisoned, the landing party escaped custody, and Osborne impersonated an Eminian guard to assist Spock in rescuing Ambassador Robert Fox from an attempt by the Eminian authorities to execute him. Osborne was also present when Spock stormed the Eminian High Council chamber, thinking to rescue Kirk, who, as it turned out, did not need that kind of help. Osborne assisted Fox in guiding the High Council out of its chambers so that none of them would be injured when Kirk destroyed war-fighting computers which the High Council had been running. (TOS: "A Taste of Armageddon")