The Vulcan elders who guide adepts through Kolinahr, the long discipline meant to purge all remaining emotion, and who judged Spock unready for its final rite in Star Trek: The Motion Picture.
The Kolinahr masters preside over the most severe of Vulcan mental disciplines, a training lasting years in which the student sheds the last traces of emotion in pursuit of pure logic. They appear at the opening of Star Trek: The Motion Picture, on a high desert plateau on Vulcan.
Spock, having left Starfleet after the five-year mission, has completed the training and kneels to receive the symbol of total logic. The presiding master melds with him, senses that his human blood has been stirred by the consciousness of V'Ger calling from space, and withholds the honour, telling him his answer lies elsewhere.
Later series return to the discipline, and Voyager establishes that Tuvok also undertook the study of Kolinahr.