This is book 4 in the DS Tyler series, it is well written and is cleverly plotted. I like the characters, especially Mina and it is good to see more of the focus on her role. Ruth was an interesting character but one I failed to empathise with despite her story. The pacing was steady throughout with some surprising revelations for Mina and there was plenty of tension. I liked the ending and look forward to reading more of Tyler and Mina in the next book. Thanks to Net Galley for my ARC.

The story starts 24 years ago, where a young girl, not even old enough to tell the time, is trapped somewhere dark with only a dog for company. She is visited by a tall skinny lady who's not very nice to her but we're given no more information at this point as to who the girl is or why she's where she is.

We then move to the present timeline, where Detective Sergeant Adam Tyler is searching an old abandoned theatre on what seems to be a flimsy hunch. No one knows he is there and he gets into a spot of bother and lands up falling. But did he fall? Or was he pushed?

Mina is Tyler's partner at work who is at a party she would rather not be at when she gets the call that Tyler has been injured and is in hospital fighting for his life. She's concerned because Tyler got himself in trouble before when he was investigating the Circle, a shadowy organisation made up of local entrepreneurs who had their own vision for Sheffield. those close to Tyler worried that he was on a personal crusade to bring the remaining unknown members of the Circle to justice.

This story is a dual timeline with half the story starting from 6 months ago, when Tyler received a cryptic letter setting about a course that would lead him to his fall in the theatre, and the timeline now, with his colleagues trying to piece together how he got to the theatre in the first place.

The story takes a major turn about three quarters of the way through that I did not see coming at all and I found myself rushing to get through the last chapters in a desperate attempt to find out the answers of how things had turned.

This book is part of a series, but I haven't personally read any of the previous books and this book is entirely capable of being read as a standalone. If anything, I was quite intrigued by Tyler and Mina's characters and would be interested to learn more about the background by reading the previous books. Tyler and Mina are both characters that don't always play by the rules and often tend to take matters into their own hands which makes them interesting to read about as you never quite know what they're going to do next.

I would recommend this book to anyone that likes police procedurals with a strong 'who done it?' theme.

If  you've read the other books in this series, you know what you're getting.
Tyler with a ton of baggage, and Mina.
This book mostly has Tyler out of action other than some flashbacks, so Mina is very much the star attraction.
It was interesting to learn a bit more about her and her background.
It has plenty of twists and turns, but I found a lot of them predictable.
I enjoyed this book, as I have the whole series, but it didn't quite live up to my expectations after the previous book.