The Various Haunts of Men by Susan Hill

Having transferred to the small cathedral town of Lafferton from London's "Met," police detective Freya Graffham explores her new community and becomes fascinated by Chief Insp. Simon Serrailler, her enigmatic superior. Though she fits well within the local police force, she finds herself unable to let go what seems like a routine missing persons report on a middle-aged spinster. When yet more townspeople turn up missing, her hunch is verified and a serious police search begins, bringing her into closer proximity with Serrailler at the same time it exposes her to danger.