Read Crossing Places first. It is not nearly as good as The Janus Stone, but you will really want the background. The narrator of this story is much better than the original narrator, who sadly got bogged down in lengthy descriptions of characters and backgrounds. Once the characters were laid out in Crossing Places, however, this book just sails along. There is a lovely balance of telling us enough to understand and visualize what is going on without tedious lectures about bones and ancient structures. The characters are mush more clearly defined and their emotions and struggles to manage the messes they have made of their lives truly make them come alive. I am so glad I stayed with the series.