5/5 for The Dying Hours by Mark Billingham, the 11th Tom Thorne book in the series that just keeps getting better. I like that the overall plot structure is moving towards a more thinking, more feeling Thorne. Even though his actions are still reckless and childish (that's why we love him!), he seems more emotionally mature in The Dying Hours.
Add a cool idea for a serial killer, mix in the usual supporting cast of friends and colleagues. Devour in one sitting.