Lieutenant Lee Kelso was a male Human Starfleet officer in the 23rd century. He served in the operations division aboard the USS Enterprise in 2265, under the command of Captain James T. Kirk. He was one of the ship's navigators. He was on a first-name basis with Kirk and helmsman Gary Mitchell, the latter whom Kelso referred to as "Mitch".
Kelso was on duty when the Enterprise encountered the barrier at the edge of the galaxy, during its mission to probe out of the Milky Way. Upon encountering the barrier, the Enterprise sustained serious damage to her warp engines, and Mitchell was affected in such a way that he began to develop extraordinary psychic abilities. Kelso visited Mitchell in sickbay, who informed Kelso that the ship's starboard impulse pack was burned out. As there was seemingly no way Mitchell could have known this, Kelso initially assumed that Mitchell was joking. Mitchell insisted, however, prompting Kelso to double-check the impulse pack, confirming that Mitchell's report was accurate.
In an attempt to repair their warp engines, the Enterprise traveled to Delta Vega, in the hopes that they could adapt some of the power packs from the automated lithium cracking station on the surface. Kelso was put in charge of the operation, and was able to successfully repair the engines.
During the repair process, Captain Kirk ordered Kelso to rig a self-destruct switch that would destroy the entire station, should Mitchell, whom Kirk was planning to strand on the surface due to his increasing instability, escape his captivity from the station's brig. Kirk then planned to meet Kelso and Dr. Mark Piper in the control room, from which they would all transport back to the Enterprise.
Meanwhile, Kelso was in the midst of a conversation with Montgomery Scott in which the chief engineer praised Kelso's ability to recognize the correct parts they needed, calling him "a talented thief." The lieutenant expressed his pleasure with the work his team had done. His conversation was interrupted by Mitchell, who telekinetically strangled him to death with a large cable in order to stop him from enacting the self-destruct.
Lee Kelso was portrayed by actor Paul Carr.
In the first draft script of "Where No Man Has Gone Before", Kelso's first name was given as "Leroy" ("Larry" for short), he was referred to as a lieutenant junior grade, and was described thus; "He is in his late twenties, pleasant-looking rather than handsome." In the final draft of the script, Kelso had the first name "Lee", had the rank of full lieutenant (no j.g.), and was described as "late twenties, a sharp and intelligent professional," details which remained the same in the revised final draft of the script.
Decades after portraying Kelso, Paul Carr remembered how he was cast in the part; "I had worked for [Gene] Roddenberry and for [Director] Jimmy Goldstone before, and they called me to do ['Where No Man Has Gone Before']." (Starfleet Access for "Where No Man Has Gone Before", TOS Season 1 Blu-ray special features)
Regarding Lee Kelso's death, a humored Paul Carr remarked, "I was – I guess, officially – the first person killed on Star Trek [....] If it hadn't been for [Mitchell actor] Gary Lockwood, I'd probably still be on that series." In fact, just before the filming of the death scene, Carr spoke to Lockwood about how he wished to remain on the series. While then being lifted in the air and violently shaken by Gene Roddenberry, the actor was told some plans for his character that, ultimately, were never realized. "[He said] 'Don't worry about it, kid. We're gonna freeze you and bring you back!' And they never did." (Starfleet Access for "Where No Man Has Gone Before", TOS Season 1 Blu-ray special features)
Herbert F. Solow expressed his judgment of the Lee Kelso role, saying it "wasn't much of a part." (Inside Star Trek: The Real Story, p. 75) Dave Rossi, VFX Line Producer for Remastered TOS, disclosed similar feelings, stating, "I think that a character that really gets a short shrift on the show [i.e. 'Where No Man Has Gone Before'] is Lee Kelso." Rossi also said of his fellow makers of Remastered TOS, "We really like Lee Kelso and, moreover, we really like Gary Mitchell's reactions to him." (Starfleet Access for "Where No Man Has Gone Before", TOS Season 1 Blu-ray special features) Chief Kelso, from TNG: "The Quality of Life", was named by writer Naren Shankar as an homage to this character. (Star Trek Encyclopedia)
It was popular belief that Kelso was the helmsman of the Enterprise while Mitchell was the ship's navigator, as suggested by their positions at the conn. However, on-screen evidence suggests otherwise. Firstly, Mitchell's responsibilities aboard the Enterprise – neutralizing warp speed and piloting the ship, for example – are those of a helm officer. Secondly, when Mitchell was knocked out of his chair after being "zapped" by the energy barrier, Kirk yells out, "Helmsman!", an exclamation aimed at Mitchell. Third, Kelso himself was credited as "Navigator" in early cuts of the episode. In this early episode, the stations are reversed: Mitchell's post was the navigator's station and Kelso's the helm station. It was never explained – either on-screen or from behind the scenes – why their positions at the conn were reversed. Kelso wore an operations division beige Starfleet uniform, even though helmsmen and navigators usually ended up wearing the gold uniform of the command division in the rest of TOS. The division insignia on his assignment patch was the stylized globe symbol that was later used exclusively for sciences division personnel.
DC Comics' non-canon biography of Kelso in Who's Who in Star Trek 1 stated he was born in San Francisco, California, and studied at the Palo Alto Technical Institute and at Starfleet Academy, where he was a classmate of James Kirk.
In IDW Star Trek: Ongoing comic "Where No Man Has Gone Before, Part 2", the Lee Kelso (β) native to the alternate reality, like his prime universe counterpart, died as a result of the alternate-reality Gary Mitchell's transformation. Instead of being strangled, however, Kelso was forced to shoot himself with his own phaser after confronting Mitchell with the weapon.