This was an enjoyable, fun book. Nothing too serious despite the fact that they are dealing with … yup, you guessed it. Grendels. The fabled monster/demon from the poem Beowulf.
Makenna Fraser is a new member of the SPI team. (Supernatural Protections and Investigations) This team is kind of like a covert ops CIA/FBI team only dealing with supernaturals. Of course not all supernaturals are bad, and many of them are part of the SPI team (including the head of the organization who is a dragon). MaKenna (or Mac as she is often called) is human, but she is also a seer, who can see beyond any veils, which is when a supernatural attempts to hide what they are behind the veil of being human. Since humans don’t know about the supernaturals yet, it can be a good thing, (to avoid complete panic among humans should they find out) that is unless you want to take out the human population, then it’s not so good.