Away team beams down to a planet, locals don't like Spock because of his brother, and Spock's all, I don't have a brother, but what's Sybok done? And it turns out that he had forced a telepathic marriage bond on one of the women in town and raped her during his Pon Farr, and now she's pregnant, and Spock has to deal with figuring out how to help her and track down his brother to bring him to justice (which traditionally would be putting him to death, but so many Vulcans have died already, but on the other hand Vulcan doesn't have the resources to deal with a prisoner and most other Federation worlds don't have prisons designed to hold such powerful telepaths as Sybok). Also, Spock has to deal with his friends and crewmates now that part of the story about Pon Farr has come out in the worst possible way.