A young Spock accompanied his father, the Vulcan diplomat Sarek, to the planet Marath to help negotiate a peace treaty. With the signed treaty safely in hand, they board the Starship Enterprise and head home. Spock is fascinated by the easy acceptance of his Vulcan culture by the bright, adventurous Starfleet crew headed by Captain Robert April and his first officer, Christopher Pike. Spock, half-Vulcan, half-human, is now torn between accepting his position at the Vulcan Science Academy or joining the cadets at Starfleet Academy.
Before he can decide, however, he and Sarek discover that not everyone is happy with the treaty. First, rebel forces attempt an assault on the Enterprise, and then Spock's own family is stalked. Spock has a hunch about who is behind the attackes. But to find out – and set the course for his own destiny – he'll have to trust his human side.