The novelization by "Phillip Rock" does a pretty good job of capturing the dark, gritty atmosphere of the film. This is Los Angeles as Hell, and both Hickey and Boggs (see photo on the book), are just about an inch away from becoming part of it. The only thing they have is their job, and even the job is "not about anything."
The action in the book, as in the movie, is outrageous, and even funny if you're in the right mood. Walter Hill did the screenplay that the book is based on, and he was really in a groove in the early '70s.
My own books have two small homages to the book and the movie versions. So small nobody but me will ever know what they are, and I'm not telling. It was great fun to sneak them in. If you haven't seen the movie, you should. The book's not essential, but it's still fun. And even after nearly 40 years, I can detect some of the differences between the two. I enjoyed reading the book again, and I've put the movie in the old Netflix queue.