10 Biggest Unanswered Star Trek Mysteries

5. The Romulan Unification

Prior to the events of Star Trek 2009, the last we'd seen of Ambassador Spock involved his extensive (and dangerous) work attempting to reunite the Romulan and Vulcan peoples. The two ancestral cousins had drifted apart in both space and culture over thousands of years, but Star Trek's most beloved son was convinced it was time to bring them back together.

He occasionally enlisted the help of Starfleet though - most notably Captain Picard and the rest of the Enterprise crew - but by the time Star Trek Nemesis rolled around the Romulan government had yet to acquiesce. Given the focus the show was happy to put on this storyline, and the fact that Spock was still working with the Romulans at the dawn of the Abrams-verse, it's clearly important.

However, neither the subsequent films really moved to answer the questions. Instead, with the destruction of the Romulan homeworld and Starfleet's apparent reluctance to aid their former enemy, it's only raised even more questions on the subject? Did the once-great Star Empire turn to their historic family for aid after the supernova, or did the Vulcan's turn their backs on Spock's legacy?