After the Fall, Before the Fall, During the Fall

Nancy Kress can be a frustrating author.

She is, perhaps, the best pure storyteller I've ever read, and that holds here, even as her tale twists across multiple times and points of view.

The problem with this book (which I'll say at the start is short and well worth your time) is that she doesn't really have a cohesive story to tell. Too many plot elements resolve to "a wizard did it" which is fundamentally unsatisfying regardless of how well she puts them together. Time travel is a strong spice, and takes a lot of a book's credibility budget - it doesn't leave a lot for possibly benevolent aliens and impossibly accurate predictive models and other magical tech.

Three stars is a little too low, but four would be too many.