This is a good, solid beginning to a new series by JR Ward. Taking place in some classic locations for readers of Ward's Black Dagger Brotherhood series, there's a lot that's familiar in this story and also something new.
For one thing, the paranormal elements are different. We do see cameos of characters from the Brotherhood world, which means vampires, but the story doesn't really hinge on them. So, we're being introduced to a new mythology, containing black magic, angels and demons. She's created a pretty good lore. Some things are left to be explained as we go along, but it's fairly easy to understand and the background left to be filled in isn't missed within the story.
Jim Heron is the main character of the series, although it seems there will be a romantic story line to each book. This one dealt with Vin and Marie-Therese (who was introduced in the BDB book, Lover Avenged). We basically had two main stories woven together with Jim learning his mission/destiny and the lovers finding and falling for each other. The two stories work really well together and the suspense, particularly toward the end, was fairly intense. With Jim still hazy on what expectations are being placed on him as well as trying to learn the tools he can depend on, I anticipate another two-story weave for the next book, as well.
My one complaint is that Ward is beginning to remind me of a singer who has a very strong instrument and a marvelous trill but doesn't know when to let a single note simply carry the moment. She's great at giving inner thoughts, philosophizing and creating analogies for the current action. In fact she's quite strong in that area. But there are moments that might be better served by just telling the story in a straight-forward manner. Just like the singer with the fabulous, skillful trill would better serve the song with a less-is-more approach, simply laying out events as they're happening might better serve the story being told. At times I felt the narrative was cluttered. But not by bad writing. Too much of a good thing that should really be used as a decorative effect. The story is strong enough to survive without the gingerbread.
Now that I've metaphored the heck out of that criticism, I can say that I did really like this book and I recommend it.
One extra thing -- I strongly implore Ms Ward to get a couple of beta readers. Continuity errors are riddled throughout and it's a problem that's also become prevalent in the BDB series. This is exactly the kind of thing that causes an audience not to commit to an author. You never know when a guy is going to drive off in the same car his girlfriend just drove off in an hour or so ago. She's got fans on her site that would do it for free. Either no editor is actually reading this or she's deciding to leave fixable errors in. Either way, she's too big an author to keep getting away with it.