I don't read a lot of historical fiction but I'm glad I picked up this one. It has it's own unique mix of romance, mystery and intrigue with a dash of the paranormal. This is the first book in His Fair Assassin series and has some tough females. A convent of trained killers in medieval France is nothing to take lightly. Ismae is a lost soul and running from an abusive life when she stumbles upon St. Mortain's. The sisters serve Death and train other young women to do the same. Ismae discovers she is a gifted assassin and is given an important assignment to protect the young Duchess from the man who will bear the Marque. A man she must then kill.The story was well written with great detail and background. Luckily I was reading the ebook version and could easily look up words I didn't know (and there were plenty). The description of the girls' training and weapons were interesting and quite informative. The tale of the god St. Mortain was intriguing and complex, unfolding slowly throughout the book. At times the story seemed dragged out and I started to drift off in the middle. The family history and politics didn't hold my attention but those aren't topics of interest for me anyway. I did enjoy the characters and how diverse they were although I did confuse some member of the royal court from time to time.Grave Mercy is not a light read and is best savored. If you enjoy historical fiction you will probably appreciate this one more than I did. The next book features a different main character's story, Sybella, who also attended St. Mortain. Dark Triumph (His Fair Assassin #2) coming in 2113www.robinlafevers.comThank you to NetGalley for an ebook in exchange of my honest review.