Ever since J.J. Abrams successfully rebooted the Star Trek movie franchise back in 2009, speculation has been increasing as to where the new Star Trek's story will head. With the entirety of The Original Series and six movies to pull material from, the second movie could conceivably go just about anywhere.
Today, trekkies and trekkers alike got their first real peek at Star Trek Into Darkness, the sequel due out next summer. The teaser trailer features plenty of smash-cuts, near-reveals, and Inception-inspired horns, but doesn't give much away. It's narrated by Benedict Cumberbatch, who plays the villain, the identity of whom fueled much of the speculation surrounding the movie. More on that in a spoilery section below the trailer.
The common rumor is that Cumberbatch will be playing Khan Noonien Singh, the villain from Star Trek II: The Wrath of Khan. However, Star Trek II is really about Captain Kirk and the choices he's made, good and bad, and how poor choices can sometimes have effects years later. The new Star Trek Kirk simply hasn't made enough of those choices for the Khan story to be meaningful. The filmmakers would have to cram the discovery of the Botany Bay and Khan's exile to Ceti Alpha V into the first half of the movie, then fast-forward over the entire original series to make Khan's revenge credible. No, it simply doesn't fit.
My guess is that Cumberbatch will play Gary Mitchell, the villain of The Original Series pilot and third episode "Where No Man Has Gone Before". In it, Helmsman Mitchell is transformed into a powerful psychic being through an encounter with the galactic barrier and has to be put down by Kirk. This story would fit well into the new Enterprise crew's early years, and the final shot of Cumberbatch in the trailer clearly shows him wearing a vandalized Starfleet uniform, implying his former service.
Also, the reveal of Alice Eve's character in the trailer shows just how much she resembles The Original Series' Elizabeth Dehner, Mitchell's eventual semi-partner in crime: