- Sky King: What's the matter, Penny? You look a little pale.
- Penny King: Flying in this rough air all day is too much for me.
- Clipper King: You know, some day, I'm going to invent a safety belt that will keep my stomach from bouncing clear up between my shoulder blades.
- Lieutenant Doug Mercer: A cold-blooded professional spy... I've read about guys like you - in my kid brother's comic books.
- Griz Raetze: We all have to make a living.
- Griz Raetze: But let me indulge my vanity for a moment and tell you how good my plan really was. I could have worked my way into some small job at Desert Project and after wasting months, or perhaps years, possibly I could have found out about a few secrets... like your American communists - the stupid fanatic fools. But this way, I waited till the complete annual reports of all the secret projects were to be flown to Washington.
- Lieutenant Doug Mercer: And now you know everything.
- Griz Raetze: Well, enough to sell for a good price to... interested parties.
- Griz Raetze: The trouble with you, King, is that you cooperate with other people. It's the lone wolf who survives in the end.
- [last lines]
- Penny King: I can't understand how a man like Raetze could think of endangering the lives of millions of people.
- Sky King: Out of a desperate fear to survive, Penny, by what he called the law of the jungle - but he was wrong. The law of the survival of the fittest has been proven scientifically false. Today, the law men like Raetze must learn to live by is the law of survival of the most cooperative.