Last Watch

Good. Not great, but good. There are a couple of in-jokes that reference the movie as a parallel reality of some sort, and there are some interesting details of Anton's home life (he's settled down considerably since the first novel). Also, Anton has progressed to the point where his boss Gesar and the antagonist Zabulon are no longer unknown great powers, but simply more experienced ones. With Anton's wife and child include, Anton's a powerful person to go against in his own right.

Will it make sense on its own? Probably not. You'll like this if you've read the previous three, but there's too much context and references to previous characters for this to be self-contained. It's good fiction.