This is the second in the Coromander Strike series. It is a very good book. Normally, I don't have much use for stories about writers since it seems like so much literary masturbation to me, but in this case it works. The mystery is about a writer who has written an autobiographical smear of literary pretentiousness that slams everyone around him. At first, Strike is just to find him but when he finds his target dead, it becomes a murder mystery.
The characters are interesting in this, particularly the highly complex relationship between Strike and his assistant. Strike is not the normal lantern jawed handsome white guy who solves mysteries, he's a flawed person but a real person with contacts and contracts and obligation. Rowling does an excellent job at hinting at the rich and complex backstory that Strike has, without wallowing in it. 90% of the prose in the book is about the mystery, and more importantly, it is highly believable how he solves it.
I highly recommend this book to both mystery fans and those who like Rowling.