And the character's name has been revealed as John Harrison - although there is already speculation that this may be a smokescreen for his real identity.
The official caption from Paramount Pictures reads: "(Left to right) Zachary Quinto is Spock, Benedict Cumberbatch is John Harrison and Chris Pine is Kirk in Star Trek Into Darkness from Paramount Pictures and Skydance Productions."
It shows Kirk and Spock looking at Harrison through a big window, which could be a jail cell.
A full trailer for the movie, directed by JJ Abrams, is expected to be released in a week - and it hits the big screen next May.
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