Third book in this series following Holy Island and Sycamore Gap. This concludes the trilogy of DCI Ryan and the circle. I loved it it was fast paced and page turning through out the whole story. I would have to say it would be a good stand alone book but I think it would be better for you to read the first 2 because there are little references to things that happened mostly in the second book but its a brilliant story. I really love the character in this series. You can imagine them all as real people, especially Ryan. I love his thinking and the fact he doesnt put up with any crap from anyone. When it comes to Anna though he is such a softy and its clear he loves her but when police work happens he is on the ball. I would totally recommend this. Love this one, its probably the best book out of the three.