I'm not going to write too much about this book because as regular readers know I am a huge fan of Fred Vargas. She writes hugely enjoyable, eccentric but layered in history (her other profession is as an archaeologist) mysteries in two series: the Inspector Adamsberg stories and The Three Evangelists. The two series also interlink characters. This is the third and final - for obvious reasons - of the Three Evangelists novels. Don't start with it if you have not read any before. Go to the first one whose English title is The Three Evangelists. I love them. I suspect some people won't. Her style is certainly individual, and the world she immerses the reader in is both recognisable and totally her own. Life would be greyer without her novels.