Spock's mother has left his father and returned to Earth with him in tow. The move brings many hardships, and soon the young Spock has to find a way to survive or end up like all the other street children. How can a homeless Vulcan child get by on the mean streets of Earth?
Spock was nearly forced by the Platonians to be the one thing he had sworn he would never again be--an instrument of harm to his captain. Soon after, Spock thought the captain was dead, trapped forever between dimensions as the Tholians closed in on the Enterprise, because of Spock's error in calculations. These events aren't as easy to get over as Spock pretends, but he should have known that he can't hide from his captain.
Between viruses, mind-melds and spores, Spock spends much of the first year of the Enterprise's mission with his mental walls broken down and his emotions out of his control. Nobody knows what it costs him to go through those events...or why he keeps letting it happen. Nobody but the one whose job it is to notice.
Takes place immediately after The Devil in the Dark, which is the episode immediately following This Side of Paradise.