Though I'm a longtime fan of science fiction, I have often found something a little formulaic about many of the classic novels of the genre. It's not with the premise -- though that can crop up from time to time -- so much as in the plot, which functioned along a certain well-worn path: man meets woman (typically in an exotic setting), man struggles (usually against seemingly overwhelming yet in the end surmountable odds), man gets woman. For a while, though, I thought I had found one of the exceptions. For much of the novel, Clifford Simak kept me guessing as to what was going on and what would happen next. It was inventive, with enough plot twists to keep me guessing as to who was who and whose secret agenda was to the detriment of humanity. Then I reached the end, and one final development came across like a cop-out, effectively reverting everything back to the formula. It was as though Simak was on the cusp of doing something incredibly daring and (for a novel written in the 1950s) literarily prescient, and then at the last moment stepped back and conformed to the formula. I can't explain more without spoiling the ending (though given the formula I described, it should be fairly evident), but it left me with a sense of disappointment that may be unfair but is nonetheless real.