I was slightly sceptical when I was given Many Waters as apresent. I had read the three other books in the series, and was seton being a purist with the trilogy. I finally gave in and read this story which took me by suprise. Her story finally gives Sandy and Dennys a chance to experience something deeper than their limited minds had allowed them to in the last 3 books. On top of that, Ms. L'Engle weaves the twins into the fictionalized "behind the scenes" version of Noah's story in Genesis, pre-flood. I finished it in a matter of two nights. This was for me, as another reviewer noted, the first realization that Ms. L'Engle is a Christian writer. I immediately re-read all three original books with a fresh understanding of the underlying idea she was getting across. It was an instantaneous blessing for me. If you like these books, C.S. Lewis' Narnia Chronicles & Space Trilogy are musts. It really doesn't matter how old you are, there are blessings in these books for the young and the not-so-young! But don't take my word on it. Read it for yourself!