Doug is an unusually ardent Vulcan specialist in the katra and a former lover of Una Chin-Riley, whose help is sought in the episode Four and a Half Vulcans.
Doug appears in the third season of Star Trek: Strange New Worlds. When a medical procedure leaves Pike, La'an, Uhura and Chapel stuck as Vulcans, cold and arrogant with it, Spock and Una turn to him as someone who may know how to bring them back to themselves.
He is nothing like the usual reserved Vulcan. He and Una parted some time ago, but the attraction between them is plain and they flirt without restraint.
To keep him at a distance, Una claims that Spock is her husband, a lie that causes its own comic trouble. Doug is played by the comedian Patton Oswalt.