This is one good mystery and adventure. We have a secret society that goes way back into our past.it deals with schemes, intrigues, their own rules, killing and stealing. At first I was a bit lost with so many information and unknown factors so I think it would be better to read this series in order from the beginning. But the author managed to clear some things later in the book.
The mystery reminded me on The Da Vinci Code with all the uncovering secrets from the past. The new Trinity is short on time to discover buried secrets that can costs their lives. The romance was not primary theme but it was ok with some kink and ménage. I liked how they interacted and get to know each other from perfect strangers to lovers. There was not much heat and passion just some hints.
I didn’t like how they, especially Caden made bdsm a bad thing. Because he was forced into it and didn’t see the other, good part of bdsm relationship and power exchange.
Overall it was a good mystery but I think I would enjoy it more if I had read previous books.