OK, no more serial killer mysteries by Josh Lanyon for me - or books where both MC's are law enforcement. Winter Kill didn't work for me at all, and now Mermaid Murders annoys me almost as much.
I think there are certain things that really bother me in a procedural type of book that I can overlook in other genres. Things like physical impossibilities - sensing when someone is looking at you, for example, or knowing a bunch of stuff you couldn't know from someone's expression or tone of voice. Procedurals are supposed to be tightly plotted and carefully constructed.
Also, the editing could use some help - people keep having the same conversations they already had, and forgetting things and re-figuring them out. I am guessing that happens when the author moves events around and then doesn't go back to make sure everything flows in the right order.
I can accept Adrian English running off to be TSTL, but it irks me when an FBI agent does it. Also Jason's boss acts like a cartoon villain. I expect him to want to kill Moose and Squirrel in a minute.
This one has really good ratings, so I'm guessing it's me and not the book.