ZARABETH: What are you called? SPOCK: I'm called Spock. ZARABETH: Even your name is strange. Forgive me. I've never seen anyone who looks like you. Why are you here? Are you prisoners too? SPOCK: Prisoners? ZARABETH: This is one of the places Zor Kahn sends people when he wants them to disappear. Didn't you come in through the time portal? SPOCK: Yes, we came through the time portal, but not as prisoners. We were sent here by mistake. ZARABETH: The atavachron is far away, but I think you come from someplace farther than that. SPOCK: That is true. I am not from the world you know at all. My home is a planet millions of light years away. ZARABETH: Oh, how wonderful! I've always loved books about such possibilities. But they are only stories. This isn't real. I must be imagining all this. I'm going mad! SPOCK: Listen to me. I am firmly convinced that I do exist. I am substantial. You are not imagining this. ZARABETH: Oh, I've been here for so long, alone. When I saw you out there, I couldn't believe it. Is he dying?
If you can't believe Spock, who can you believe?