The idea was quite intriguing. People who could travel between parallel worlds by interacting with "Ley" lines. These are apparently associated with what is called "telluric energy" that are lines of electric current that travel through the Earth's crust. Some have speculated in fiction that these currents can allow one to travel to other dimensions, worlds, etc. It makes for a great story. I was also interested in the way that the so-called "skin map" came to be. One of the characters, Arthur Flinders-Petrie, a seasoned ley traveler, learned how to map the various parallel worlds using the leylines. In order to keep his discoveries from falling into the hands of evil people, he had it tatooed on his body. Apparently, after his death the skin was removed and preserved. Voila, the Skin Map. The story followed the travels of others who were searching for the map, or for missing persons, or for true love. All the while trying to stay one step ahead of the master villain, Lord Archelaeus Burleigh, Earl of Sutherland. Even the name sounds nasty. All in all, a good basis for a fantasy novel.
However, this book missed the mark by a fair amount. While the idea of travel throughout the time-space continuum has received a fair amount of attention, this book promised something new. It was not. Many of the possible story lines were not resolved with satisfaction. Flinders-Petrie, in an attempt to save his young wife's life vowed to take her to "the Well of Souls." The what? This was not developed at all. The reader was simply left hanging. OK, I understand the concept of building tension, but there needs to be some resolution.
Perhaps the author was trying to keep to many storylines in play. However, what interaction there was seemed to be contrived and unnatural. The ending, rather than giving the reader either satisfaction at the resolution of these storylines, or at least providing a good cliff-hanger that would make one want to read the next installment, simply fizzled out like a firecracker dud.
I expected more from an author of Lawhead's ability. Maybe he needed to meet a deadline. I don't know. What I do know, however, I cannot recommend this book.