In Star Trek V: The Final Frontier, who is the Vulcan extremist?

In Star Trek V: The Final Frontier, the Vulcan extremist is Sybok.\n\nSybok is a Vulcan who rejects the traditional discipline of suppressing emotion. Instead, he uses powerful telepathic abilities to confront people with their deepest fears and pains, promising them relief through emotional release. His methods and beliefs place him outside mainstream Vulcan philosophy.\n\nThe film establishes that Sybok is Spock’s older half-brother. Sybok was born to Sarek and a human woman, while Spock was Sarek’s son with Amanda Grayson. Their family connection helps explain why Sybok can persuade Spock and why Spock is drawn into the crisis despite distrusting his brother’s goals. Sybok hijacks the USS Enterprise-A and leads a search for the supposed deity Sha Ka Ree, a mythical place at the galaxy’s center.\n\nThe other choices are different Vulcan figures: Spock is Sybok’s half-brother, Sarek is their father, and Surak is the ancient philosopher credited with establishing Vulcan logic and guiding his people away from violent emotion. The 1989 film was directed by William Shatner.