Star Trek II: The Wrath of Khan
William Shatner ... Admiral James T. Kirk
Leonard Nimoy ... Captain Spock
DeForest Kelley ... Dr. Leonard "Bones" McCoy
James Doohan ... Cmdr. Montgomery "Scotty" Scott
Walter Koenig ... Pavel Chekov
George Takei ... Hikaru Sulu
Nichelle Nichols ... Cmdr. Uhura
Bibi Besch ... Dr. Carol Marcus
Merritt Butrick ... Dr. David Marcus
Paul Winfield ... Capt. Clark Terrell
Kirstie Alley ... Lt. Saavik
Ricardo Montalban ... Khan Noonien Singh
The Enterprise has become a training ship under the command of Spock. And Kirk can't handle the fact that he getting old. But suddenly Kirk gets an emergency call from an old girlfriend because someone's out there who wants to even the score.
My opinion:Khan is the best advisary a Starfleet captain could wish for. Only General Chang can level with him and both happen to have an interest in english literature.

As to Spock: As much as I hate it when they kill good characters I have the utmost respect for someone who can apply the third principle of sentient life*.
In my opinion there is a logic hole in the movie (although only a Trekkie would think of it) when it comes to Genesis: I can't imagine that the Federation would really be willing to let the Genesis experiment go so far. The arguments McCoy used must have come up earlier and they had to see how dangerous such a thing could be.
*The third principle of sentient life is the capacity for self-sacrifice, the conscious ability to override evolution and self-preservation for a cause, a friend, a loved one.