I'm reading Lisa Jackson's Left to Die, about a killer in rural Montana who shoots out the tires of cars during blizzards, causes them to crash, "rescues" the lone driver (always a woman), gives them remedial medical care to heal them up, and then days later they're found naked, tied to a tree and left to die in the freezing temperatures. He's been leaving a clue at each tree, with their (combined) initials, spaced weirdly so that it looks like he's slowly spelling out a message of some length. The novel has a two-female-detective force trying to solve the mystery of who's been killing these women, as the killer finds a potential fourth victim and makes ready to start the cycle all over again.
Johnathan