An official plot synopsis of Star Trek 2 aka Star Trek Into Darkness has been revealed by Paramount:

Star Trek 2 Into Darkness Movie Trailer

Plot:
“In Summer 2013, pioneering director J.J. Abrams will deliver an explosive action thriller that takes Star Trek Into Darkness. When the crew of the Enterprise is called back home, they find an unstoppable force of terror from within their own organization has detonated the fleet and everything it stands for, leaving our world in a state of crisis.
With a personal score to settle, Captain Kirk leads a manhunt to a war-zone world to capture a one man weapon of mass destruction. As our heroes are propelled into an epic chess game of life and death, love will be challenged, friendships will be torn apart, and sacrifices must be made for the only family Kirk has left: his crew.”

The film is directed by J.J. Abrams (who helmed the first film) and is starring Chris Pine, Zachary Quinto, Zoe Saldana, Simon Pegg, Karl Urban, Anton Yelchin, John Chu, Bruce Greenwood and Benedict Cumberbatch. The official release date of Star Trek 2 Into Darkness is set for May 17, 2013.
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