- Control Voice: [intro] Rocks. Silent, inanimate objects torn from the Earth's ancient crust, yielding up to Man over the long centuries all that is known of the planet on which we live, withholding from Man forever their veiled secrets of the nature of matter and cosmic catastrophe, the secrets of other worlds in the vastness of the universe, of other forms of life, of strange organisms beyond the imagination of Man.
- Control Voice: [epilogue] Two black crystalline rocks, unclassifiable, objects on the border between the living and the nonliving, a reminder of the thin line that separates the animate from the inanimate, something to ponder on, something to stay the hand when it reaches out innocently for the whitened pebble, the veined stone, the dead, unmoving rocks of our planet.
- Dr. Jonas Temple: You are a danger to us. You may think now that it is your own madness, but you're too rational a man to remain irrational for long.
- Caretaker: This terrible fever changes people, señor. I have seen it many times. It moves with swiftness. My own wife, I leave her well and happy one evening, and in the morning I do not know. The young have the look on them of old people. The beauty leaves the face of the women. Señor, it is death putting the finger on those it will claim.
- Dr. Jonas Temple: Been in surgery all morning, Paul?
- Paul Cameron: Yeah. It seems more like all day.
- Dr. Jonas Temple: Tough operation, huh?
- Paul Cameron: Had some bad moments, but the patient, thanks to his iron constitution, is still with us.
- Dr. Jonas Temple: Yeah, but I think I'll stick to my rocks. They never get sick, and they never phone me in the middle of the night.
- Rock #1: The time is here.
- Rock #2: We have come to the day.
- Rock #1: It has been a long waiting.
- Rock #2: A long waiting but over now, and time to invade the bodies of these things called human beings. Someone is present. Is it safe for us to communicate?
- Rock #1: Only our own kind have the power to hear us.
- Rock #2: Looking at him, I'm filled with apprehension. Can the fragile corpus of these Earthlings support our consuming energies?
- Rock #1: Some will withstand body invasion. Others will deteriorate. We must choose the hardiest specimens.
- [Paul slowly revives]
- Rock #1: Not that one. There's something wrong with his head. He's defective.
- Rock #2: Will we be able to manipulate the intelligence and the memory?
- Rock #1: Once we inhabit the host, our control of the whole multicellular organism will be complete, and then we can begin to control their planet.
- Paul Cameron: Kind of warm for burning fires, isn't it? Is it a ritual?
- Caretaker: The fires keep away the possessed, señor.