I sat there letting my coffee grow cold because all the time I was thinking that the one thing in the world John Kelley didn't possess was a sense of humor. As long as I had known him he had never told a joke and came damn close to never laughing at any.
"I don't recall any reports of anybody running around with six arms or green skin or tentacles instead of limbs," I protested mildly.
He shook his head, deadly serious. "You're not looking at it logically, Charley. The only beings who would be interested in the planet in the first place are beings who could live here. And if they could live here, then it's possible they could have the same sort of physical make-up." He paused. "Maybe the exact same sort of physical make-up. Even to the extent of the average man's desire to avoid trouble."
Kelley had something there. Every time you think of an invasion from outer space, you think of a hundred huge rocket ships settling down with ray guns going full blast and king-sized atomic bombs breaking up the landscape. Actually, of course, it doesn't have to be like that at all. Granted a physical resemblance in the first place, then maybe it wouldn't be an invasion. It might be more of an ... infiltration.
I jerked my thumb towards the people who crowded around the train gates and sprawled out on the benches. "You mean that some of those people aren't ... genuine?"
"That's right," John said slowly. "Some of them aren't the real McCoy."
I watched the people for a moment more, staring hard at the old man buying a paper at the newsstand and the old woman who was selling it to him.
"How can you tell which are which?"
"I can't. So far as I know, there isn't any way."