Star Trek: The Original Series - Tome 82 : Star Trek: Mind Meld

Teska, a Vulcan child raised on Earth, is destined to play a crucial role in the reunification of the Vulcan and Romulan peoples. While Spock escorts his young niece back to Vulcan for her betrothal ceremony, he strives to help her understand both her Vulcan heritage and her growing telepathic abilities. But when an unplanned mind meld reveals the true identity of a deadly assassin to Teska, she and Spock find themselves the target of a Rigelian criminal network. With the EnterpriseTM light-years away, Spock and his niece must go on the run, pursued by a conspiracy determined to end teska's future before it has even begun.