Lieutenant Johnson is an Enterprise security officer in Day of the Dove who is wounded fighting Kang's Klingons, heals unnaturally fast and then defies Kirk in his eagerness to kill.
Lieutenant Johnson serves in security aboard the USS Enterprise in the Original Series episode Day of the Dove. He goes down to Beta XII-A with the landing party and is present when Kang's Klingons are brought aboard and the ship's weapons turn into swords.
In the running fights through the corridors Johnson takes a wound that ought to be fatal. Like every other injury on the ship it closes within minutes, the work of the energy being that feeds on hatred and wants its food supply kept alive.
Patched up, Johnson storms out of sickbay intent on revenge. Kirk orders him to stand down and he refuses, attacking his own captain until he is subdued. The incident is one of the things that persuade Kirk and Spock that an outside force is driving both crews.