A colonist from Deneva who piloted a small ship straight into the system's star in 2267 and, moments before burning up, cried out that he was free of the parasites.
Kartan appears only as a voice in the episode Operation: Annihilate!. As the Enterprise nears Deneva, following a trail of mass insanity across several worlds, sensors pick up a one-man vessel heading directly for the Denevan sun.
Kirk tries to catch it with a tractor beam but the ship is too close to the star. Its pilot does not answer hails until the last moment, when he shouts joyfully that he has done it and is free, and is then incinerated.
The incident puzzles the crew until they find Deneva overrun by flying neural parasites that control their hosts through pain. Kirk remembers the pilot's words and reasons that something about the sun killed the creature inside him, which leads to the discovery that intense ultraviolet light destroys them.