Nicholas Hood's chosen theme for his paintings is violent death. While his work is much admired for its technical skill, it lacks heart/insight/passion. So, in fact, does the artist who is married to an impossibly sweet and lovely musician (harpsichord). Everyone in the book is far too tolerant of this unpleasant man who becomes ever more unpleasant exponentially once he's made his "deal with the devil."
The writing is fine; the subject matter is merely unpleasant and not particularly revealing. Although the one truly inspired aspect is that as Hood becomes exposed to more and more violent murders, courtesy of Bellisle (the "devil" of this tale), Bellisle becomes, to Hood's eyes, more and more handsome. This is a very well conceived corollary: that the more attractive something becomes to a person, the more attractive becomes the purveyor or facilitator of that particular something.
Otherwise, while all the secondary characters are well-drawn and sympathetic and, no doubt, the author intended us to dislike Nicholas Hood, unfortunately he's so dislikable that it makes for difficult reading. This makes Blunt's progress as a writer notable, because Forty Words for Sorrow is one of the best books I've read in a long while. Cold Eye is worth reading for its value in tracking the growth of the writer. And I expect some horror fans might find it very entertaining.