This was really more of a three-and-a-half than a four but I'll round up because it's Lanyon.
I think maybe the reason these Holmes & Moriarity books aren't as good for me as the rest of Lanyon's books is that Christopher reminds me so much of, well, me. And I don't really like him, which makes me feel all kinds of uncomfortable. And I really don't like J.X.'s controlling nature either - it's something I would not be able to live with in a million years.
In this one, the mystery didn't really seem to be up to par, either. Maybe because there were so many elements to the eventual plot, so many characters playing a part without seeming altogether necessary. Sometimes less is more even in mysteries.
But I did finish the book in two days, which is quite fast paced for me these days, so I suppose not all hope is lost. Most likely it's just a case of way too high expectations, a consequence of having a favorite in any genre. I've come to expect entertaining and riveting reads from Lanyon, so anything less will always dissapoint.