3. Spock
That Leonard Nimoy offers the definitive Spock is not an issue for debate here or anywhere else - Nimoy is Spock, just as Spock is Nimoy, and Abrams wasn't stupid enough to try and scrub away the legacy of the actor entirely, casting him in his new universe as the major link between the two iterations. Abrams also seems to have identified Spock as the heart of change - every other character seems to be at least partly a walking homage to the performances that came before them, and the same can be said of Quinto's outward performance as Spock. There is certainly something of the mimic in his performance (though of course there is only so much any actor can bring to a Vulcan) but under the surface, Spock is an entirely different animal in Into Darkness. The events of the narrative give Quinto the opportunity to push Spock's human side to the front - yes, the decision to explore the relationship with Uhura is less successful, and feels superfluous (though of course necessary thanks to the last film,) but the sight of Spock wrestling with his human emotions late on in the film unleashes a side of the character we have never seen. And in Quinto's hands, that Spock is irresistible, and just as in The Wrath Of Khan it is he who propels the narrative towards its conclusion, though in entirely different ways.