The unnamed Romulan commander who duels Kirk across the Neutral Zone in Balance of Terror, a weary professional who gives humanity its first look at a Romulan.
The Romulan Commander leads a Romulan Bird-of-Prey armed with a cloaking device and a powerful plasma weapon across the Neutral Zone in Balance of Terror. His ship destroys several Federation outposts in the first test of Earth defenses since the Earth-Romulan War a century earlier.
When the Romulans appear on screen for the first time, the crew is startled to see that they closely resemble Vulcans, a revelation that briefly stirs suspicion of Spock. The Commander proves a thoughtful and battle-worn opponent who respects Kirk, mourns the old friend who serves as his centurion, and carries out a war he has come to doubt.
After a long cat-and-mouse battle, his crippled ship is left at Kirk's mercy. He tells Kirk that in another reality they might have been friends, then destroys his vessel rather than be captured. He was played by Mark Lenard, who later played Sarek.