This review was first posted on http://www.rubysreads.com. 
 I discovered the Mercy Thompson series in 2010, after Silver Borne had been released in hardcover. This meant that I was able to devour books one through five in quick succession. And I mean quick. I've loved Mercy since the moment I met her. I'd doubted I would because the cover...well, it doesn't really capture the Mercy of the books. I've read on Briggs' website that the cover art is a glamorization of Mercy, that despite her tattoos, she's more girl-next-door than biker chick. It's true. Cover Mercy wears stuff that practical, down to earth Mercy wouldn't be caught dead in. Take the cover of River Marked. I can say for absolutely certainty that the likelihood of Mercy wearing a tube top and a fringed vest is nil. As a mechanic, she would object to the impracticality of a top that could slide down at inconvenient moments and the fringe would certainly get caught while she was under the hood of a car. Still, the covers evoke the story--the cave paintings are not accidental, and neither are the feather earrings or the vest. They're there because this is the book in which we finally get to explore Mercy's Native American heritage, and how she came to be born with the ability to shift into a coyote. 
 River Marked follows Mercy and Adam on their honeymoon to Columbia Gorge. They have a borrowed souped-up trailer and a posh campground all to themselves. I'll spare you the details of their wedding and let you enjoy that for yourself. Mercy and Adam only have a few blissful days, however, before the usual kind of trouble finds them. First Mercy sees the ghost of her father performing a native dance. Then, in the middle of the night, she and Adam rescue a Native American man from the river. But it's not a simple accident--the man and his sister were attacked by a river monster that no longer lies dormant. It has been awakened, and awake, it is hungry, and its mark compels people to bring it more food. 
 River Marked deals with Mercy and her heritage, and a supernatural creature. There are also appearances by the Native American gods, and other walkers. But the heart of this story is Mercy and Adam working out the kinks of their relationship. Adam is Alpha. He can't help it. It's his nature to be protective, even though he realizes that Mercy needs autonomy. She needs to make choices for herself and she needs to take risks if she deems them worth their outcome. I think she also wants Adam to understand that she can't sit back and let him take all the risks, either. The fact that the monster in this story lives in water--a sphere where werewolves are useless--means that Mercy has to face the danger this time. But Mercy also understands that, as a werewolf, there are things that Adam needs, too, and that possession is a two-way street. He's hers as much as she's his. That's the only way it can work. Marriage doesn't miraculously fix Mercy and Adam's relationship. It would be completely unbelievable if it did, and all too often, that's the message Romance novels project when the happily ever after ends with a wedding. I'm looking forward to the kinks and curves this relationship. It's not as fun as the journey to bring them together, but it's still wonderful. 
 But. Yes, there's always a but, isn't there? I was disappointed that, because this story takes during Mercy and Adam's honeymoon, we didn't get to see much of the other characters. We get to see Warren, Kyle, Darryl and Jessie very, very briefly. We're used to brief glimpses of Bran (who exerts his usual mesmerizing effect on everyone), but I can't wait to see what it's going to be like now that Mercy is a member of the pack. The issues of pack politics are going to be deliciously delicious. I'm also really looking forward to seeing more of Jessie and Mercy's relationship. I can see that they're going to have lots of fun at Adam's expense, and that Jessie is going to have plenty of fun at Mercy and Adam's expense, too. I'm also hoping for an eventual meeting with the ex-wife. I was also frustrated by the ending. Mercy's medical bills must be astronomical. Does she have to finish each installment with serious injury? All those broken bones are going to come back to haunt her in old age. 
 Over all, however, I loved this book. I was enthralled by the appearance of Coyote, of all the Native American gods. I'm now ready to begin the interminably long wait for book seven.