- Narrator: [Opening Narration] The Florida Keys - two astronauts, on pass, marlin fishing. Eight days before the launching of the United States' first moon shot.
- Narrator: [Act One Narration] The nation has been stunned. The first screaming newspaper stories spoke of a fishing accident and the strange, red fog. Two men, slated to walk on the face of the moon, had unaccountably perished. For David Vincent, there was an answer, terrifying in its implications. And so he came to the Florida Keys to find the radio operator who had heard the vacationing astronauts' final words.
- Narrator: [Epilog Narration] In the far reaches of outer space, the Invader reorganizes his plan for the conquest of the Earth. He's been delayed - but he hasn't been beaten.
- Gavin Lewis: What are you going to look for when we get to the Space Center? One of these... aliens? And what's he gonna do, come up and introduce himself? You told me yourself, they look the same as we do.
- David Vincent: There are ways of recognizing them. First of all, they have to regenerate themselves. And they have an awkwardness about the hands, there's a... mutated fourth finger. And the fact that they have no heartbeat.