- Susan Foreman: One day, we'll know all the mysteries of the skies... and we'll stop our wandering.
- Barbara Wright: Then you and I will say goodbye.
- Susan Foreman: Mmm? Oh, not yet! Not for a long time.
- Marco Polo: To make matters worse, the old Doctor continually shows his disapproval of my action by being both difficult and bad-tempered. For three days now, during which time we have covered no more than thirty miles, I have had to endure his insults.