Since I have no knowledge of like crimes done in England and Canada the book wasn't spoiled for me.
It was a chilling read altho as someone pointed out already, somewhat repetitive in places.
While I agree with others who liked the book overall and found it hard to put down, I also had to wonder why a cop would feel any remorse for killing a complete non-human as Lise does toward the end of the book.
This was not a "predictable" story for me. The mystery was in the chase as well as the question of being able to save the last victim in time.