3.5 I am not completely sure of what to make of this book. It was compelling because it makes you think about all the possibilities, as far out as they could be. And I was perfectly happy with this book, up until Sally enters the picture. I just could NOT stand her at all. She was so...arrogant, and bratty. She is in her thirties for god's sake, she is not a child. Actually she is worst than a child with all her petty jealousies. So for the first 3/4ths of the book I would have given it a 4, really loved hearing how it affected earth and how it all came about. The last 1/4th, even though it talked more about evolution and the pondering of the whys, Sally just ruined it for me. Some people will probably not like all the theorizing and the pondering of the mysteries of the world, because that is basically all that you will find in this book. There is almost no actual action. There was like 1 fighting scene with some elfs and funky dogs, but that was it. But I actually enjoyed this book even with the unfortunate appearance of Sally.