Sybok. (Laurence Luckinbill).
Son of Sarek of Vulcan and half-brother to Spock. Sybok was born in 2224 to Sarek and his first wife, a Vulcan princess. After the death of his mother, Sybok was raised with his half-brother, Spock. Even as a youth, Sybok was a rebel in the highly conformist Vulcan society, and he was eventually ostracized because he sought to find meaning in emotions as well as in logic. Sybok left his homeworld to pursue his visions of the mythical planet Sha Ka Ree. Sybok did not realize that these visions had been implanted by a malevolent creature living near the center of the galaxy. This creature inspired Sybok to gather a group of followers at planet Nimbus III in 2287, then to hijack the Starship Enterprise-A to the planet it called Sha Ka Ree, in hopes of using the starship to gain its own freedom. Sybok perished at the planet he believed was Sha Ka Ree, having realized too late the malevolent nature of the entity there. (Star Trek V: The Final Frontier).
- Star Trek Encyclopedia
Sybok was also able to control people's emotions by sort of mind melding with them. He was able to project an illusion of McCoy's dying father (McCoy's greatest fear) and convince McCoy to fight his fear. This allowed him to persuade many of his followers.