I really LIKED this book, but I did not love it nearly as much as the books in Madeleine L'Engle's original Time Quartet. However, that is not saying the book is less than good. It is a wonderful coming-of-age novel focusing on the original Quartet characters' daughter, Polly O'Keefe (also in other L'Engle works) and her friend Zachary Gray (also in other works). As they travel back to prehistoric time from her grandparents' swimming pool and the famous star-watching rock, they learn about the true meanings of love, sacrifice and loss.