captainvulcant:

“Well, of course they put in a little footage at the end of the movie that suggested that this might not be the end of Spock. And they came to me, sure enough, after the picture opened and did business, and they called me in for a meeting.
They said ‘We’d like to know if you’d like to be involved in another Star Trek Movie?’.
And I said ‘Yes, I’d like to direct it.’”

“For The Love Of Spock”
Adam Nimoy
455 Films