I am a huge fan of Heather Graham and the Krewe series. I really love the audio books of this series but any form will do for me. I also don't mind if I read them out of sequence. Yes she adds new members and new loves to each book, and does hint at previous books in the series but these can be read as stand alones as well.
In the hidden we meet Scarlet. She is Agent Diago's ex wife. Scarlet is living in Colorado. She lives over a museum owned by some old friends who also own the bed and breakfast next door. One day she is out relaxing and taking photos. When she goes to show her friend the picture of a large animal in it's place is a picture of a dead couple. Almost immediatly the pictures delete themselves from the camera. Later that evening while she is out a couple really end up dead in the exact spot and the exact way as n the picture. She is then hauled into the police station for questioning, since she did have pictures of the scene on her camera before the bodies were found. She then calls Diago to come help her out of this mess.
Diago is a policeman in Miami. He has been invited to be a Agent in the Krewe but has not decided to join yet. Until he gets the call from Scarlet. Diago and the Krewe come to her rescue. After arriving they find tha the killings are not over yet. It is up to the Krewe to use their special powers to solve the murders as well as murders from the 1800's also on the same land.
Once I started this book I couldn't put it down. It was actually one of my favorite books of the Krewe series so far, and I have loved them all.