In short: With an intriguing premise and a strong heroine, Grave Mercy by Robin LaFevers is sure to enchant readers. 
 You know that when a book features nun assassins, it has got to be a good one. Seriously, how cool is the premise for Grave Mercy? Girl, trained to be an assassin by a group of nuns and to serve Death Himself - it's creative, it's intriguing, and it's incredibly strange, but also obviously awesome. To add to that, Grave Mercy is one of those books whose first few pages are made up of a map and an index of characters to keep track of things. Automatic win. All these factors indicated that Grave Mercy would have a complex and attractive plot, and as it turns out, it most definitely did. 
 Ismae was the strength of Grave Mercy for me. Even coming from such a dismal upbringing, abused first by her father and then by her husband, she maintains a remarkable and admirable strength of character. Once she is taken in by the convent of Mortain, she is trained in the art of combat, poison making, and seduction, all in the aim of making her an effective killing machine. She serves as a loyal handmaiden of Death, sometimes blindly following the orders of the convent, taking people's lives without question. 
 It is only when she meets Duval, a Breton noble who is a lot like Ismae in his practicality and strength, that she begins to doubt what the convent has taught her. Maybe her purpose as Death's handmaiden isn't to be a killing machine after all, but instead as something much more important and meaningful. I loved seeing Ismae come to this realization and develop as a character throughout Grave Mercy. And I adored Ismae and Duval's slow-burn relationship as it developed, starting out in a place of distrust and then slowly moving to a place of mutual respect and gradual affection. 
 At 549 pages, Grave Mercy really flew by, except perhaps in a few sections in which discussion of the politics behind who the Duchess of Brittany should marry dragged a bit. Other than that, Grave Mercy maintains a fast pace filled with action and intrigue that will captivate the reader. Grave Mercy is my first Robin LaFevers book and I don't plan on it being my last. I'm a bit disappointed that the next two books in the His Fair Assassin series, Dark Triumph and Dark Hope, will not feature a return to Ismae and Duval's story but instead will showcase the lives of two other girls from the convent, but I am hopeful that they will make an appearance at some point.