With a good director and a decent budget, 24 Bones would make a pretty cool action movie. As a book, however, it has some issues, one being that the writing can at times be somewhat difficult to follow and at others a bit grating. And then there's the fact that, in spite of the large amount of potential material, it was all squeezed into a single relatively short novel, so certain things are rushed, not being properly explored or explained, coming more or less out of nowhere or being too fortunate or otherwise questionable even if the premises are accepted.
Still, those questionable parts do tend to be mainly details, as the story is otherwise internally consistent and does give the impression of being properly researched, though I'm not exactly in a position to judge the accuracy of some of its supposedly more realistic aspects. Also, and fortunately for me, said realistic aspects are left mainly in the background, more specific elements being used sparingly, largely only to establish the time and place, so this is a case of urban fantasy where the fantasy aspect clearly dominates.
One final note, however, is that the story makes it clear from the beginning that the opportunity for this to happen appears every 500 years. As such, humans being humans, it only makes sense that it was attempted every 500 years. Of course, it may have failed every single time, it may have been stopped relatively early in the past, and the world at large may not have heard of it, but signs should have remained and they should have been discovered by the characters. And, while this is another likely positive element for that movie I mentioned, if past attempts didn't cause permanent damage, this one probably shouldn't have either.