Good sequel. Some nice character development, esp. for Kate and her brother. Chip and Alex remain slightly underdeveloped. The historical aspect and the idea of all those missing/ mysteriously dying kids in history having actually been saved is an interesting idea, though the science aspect is laughable. Also, the ethical overtones in this series seem more sound than that of her Shadow children sequence. Leaves with them starting off on another mission/adventure through time, while still not knowing where Jonah is supposed to be from and why he was taken. Until I can read more of the series, I really have no opinion on this as a whole. Ok, but it needs something more.