The fourth book in the series started by Madeleine L'Engle with A Wrinkle In Time. This book isn't exactly a sequel, rather, it follows the adventures of two minor characters from the other books, the identical twins Sandy and Dennys Murry, when the accidentally trigger a time machine and find themselves among the family of Noah just before the Great Flood. Assorted seraphim and nephilim round out the cast and give it a supernatural flair.

The title is taken from a Bible verse, Song of Songs 8:7: "Many waters cannot quench love; rivers cannot wash it away. If one were to give all the wealth of his house for love, it would be utterly scorned." A good read overall, and not so theological that a non-Christian couldn't enjoy it plenty.