What red herrings did you pick up on, either while reading or at the end of the book?
Part of me was surprised that the killer was the FBI agent. That said, it made sense because he visited the killer so many time in prison. What happend to that man that he decided to continue the killing? Who knows?
The author wanted us to suspect that Anna was the killer by making us doubt her motives, and also by the fact that she seemed to black out or lose periods of time every once in a while. Plus her affinity with the forest made her seem more like her father.
Two big ones were Anna herself being the killer, which I think I sort of leaned on (but didn’t fully believe) for a chunk of the book. Julie mentioned the large gaps of lost time, which definitely made me suspect her. The other, though maybe more obvious red herring, would be Cas. He was the perfect person to blame it all on, especially with his affinity with the original Strangler’s “work.”
I never really bought Anna as the killer. That would have been too easy. On the other hand, I was definitely leaning toward Cas as the killer for a significant chunk of the novel. I also wanted to believe that the ambulette driver was more involved.