Mr. Spock: Doctor, your poor attempts at humor exasperate an already desperate situation.
Dr. Leonard 'Bones' McCoy: I don't think I like you.
Commodore Matthew Decker: [on video tape] Commodore Matthew Decker. This is my report. If you're watching this tape, it means someone from Starfleet has come looking for me. I'm betting it's Jim Kirk. But whoever it is, I'm sorry I missed seeing you.
Commodore Matthew Decker: [on video tape] How many other men can say that they have seen three centuries?
Commander Kargh: [about the Guardian of Forever] You have studied it, of course?
Dr. Macgregor: Not as much as we'd like. To tell you the truth, we're a little afraid of it.
Mr. Spock: That is wise.
Captain James T. Kirk: Opinion, Doctor?
Dr. Leonard 'Bones' McCoy: I think you're a damn fool. And that guy with the ears is even worse.
Captain James T. Kirk: I'll take that as a yes, then, Bones.
Captain Christopher Pike: I'm getting pretty damn tired of waiting for this Captain Kirk.
[referring to the Doomsday Machine]
Captain Christopher Pike: Let's send that monster back where he came from.
Dr. Leonard 'Bones' McCoy: All this, for a history we don't know, for people we may or may not become? Captain, call it off while you still can.
Captain James T. Kirk: [referring to the Doomsday Machine] I don't want that thing to have any trouble finding us at the supper table.
Captain Christopher Pike: [on viewscreen] Kirk, what the blazes are you doing?
Captain James T. Kirk: Saving the future.
Captain Christopher Pike: [on viewscreen] Not alone!