Star Trek III: The Search for Spock - Movie Synopsis & Plot
In the aftermath of Khan's death, Kirk is not feeling victory. Spock is dead and McCoy is going insane. Somewhere, though, there is an explanation for it all, and Sarek, Spock's father, has the answer. McCoy, the last person to have touched Spock, is possessed by the living essence of the dead Vulcan.
Kirk realizes that his only option is to defy Federation law and go to Genesis by stealing the USS Enterprise. Unfortunately, things will not be so easy. The planet is falling apart, literally, and the Klingons are planning on intercepting the Enterprise in a deadly showdown.