1800s Korea and the persecution of Catholics was an entirely new setting/topic for me, and I appreciated learning about it through the eyes of Seol, who was an engaging narrator. I did find it hard to keep track of all the characters and their connections throughout the story (I wish there'd been a character list provided!). There was a long section in the middle of this book that dragged, but the ending made up for it, pulling things together and feeling finished without being overly happy or artificial. While the middle lulled, the intensity ratcheted up in the last several chapters, making it hard to put down at that point.
All in all, a different sort of historical murder mystery from most of the offerings in YA, and well worth the read as long as you are willing to be patient.
4 shooting stars.