McDevitt's talent for imagining intriguing scenarios, asking what would hapen if... ?, and then fleshing out what interesting people would do if is I think unmatched today in science fiction. Ancient Shores is an engrossing book, without hardly any explosions or magic handwavium sci-fi plot helpers. It's ending is abrupt and ultimately unsatisfying enough to cost the book a star, but it's nothing that will ruin the experience of having read an accomplished storyteller with a bright and keen imagination telling you what would happen if. I have a fuller review up on my site, but the jist is the same.