Just over a year ago, Captain James T. Kirk was lost in the Nexus while saving the USS Enterprise-B from destruction. Aboard the science ship USS Intrepid II, Captain Spock, commanding some of his old crewmates, must face the loss of his closest friend. But while still in mourning for one friend he must come to the aid of another.
Spock's childhood friend David Rabin, now a captain, has been assigned to a harsh desert world much like Vulcan, where the Federation is determined to protect the lives of the inhabitants. But Rabin's efforts are being sabotaged and he has asked for Spock's help against the unknown forces that may destroy the society he has come to save.
While reflecting on his youthful adventure with Rabin – the adventure that set him on the path to Starfleet – Spock joins with him to face an enemy out of their shared past and confront deadly Romulan treachery. In the process, Spock will decide if the path of his life now leads back toward the family traditions he had once sought to escape.