Borderline by Nevada Barr
I have been enamored with the "Anna Pigeon, Park Ranger" mysteries by Barr for since college, and always look forward to a new adventure with her and a new park to explore.
This time, Anna and her husband Paul are on leave, and decide to take a rafting trip up the Rio Grande in Big Bend National Park - but when a dead body, a mysterious shooter, and an unraveling mystery threaten them all, Anna must step up to solve this twisty, turny mystery.
Once again, Anna proves to be a wonderful protagonist - strong but flawed, determined but at times, terrified. This was definitely an "edge of your seat" title - though the action part ends halfway through the novel, the story definitely doesn't end there. And I didn't see the end coming...
Anna Pigeon remains one of my favorite characters in fiction, and this is another great addition to her series. I can't recommend these "out of the ordinary" mystery novels enough! Great!