After the death of Captain Kirk aboard the U.S.S. Enterprise 1701-B, the crew of the original Enterprise must find a way to go on without their long-time leader.

Captain Spock, still stung by the loss of his closest friend, is forced to action when an old enemy from his childhood resurfaces with a plan that may destroy a world.

To save a planet, Captain Spock must review the most difficult choice of his life and make the toughest decision of his Starfleet career.