The Library at Mount Char, by Scott Hawkins

This is a pretty spectacular book, but probably isn't for everybody due to the level of gore. It's also rather difficult to describe, but here goes: The Library houses twelve main areas of study, all collected and collated by Father, a man of incredible age and unspeakable cruelty. Father gathered twelve children on Adoption Day, the day their parents all died, and each child has mastered his or her subject: death, healing, languages, war, etc. Now in their early thirties and familiar only with the insular yet vastly knowledgeable world of The Library, the unimaginable has happened: Father has been killed, but no one knows how or by whom. We follow mostly Carolyn, one of the twelve, and it quickly becomes apparent that she is planning something special all on her own.

This is the kind of book I'd love to see turned into a movie, but am so appreciative that it wasn't obviously written with that in mind. There's a good amount of action and violence, while the characters are astonishingly stark and well-drawn despite their alien natures. I found myself deeply invested in the outcome, and sped through the book in a single day (phenomenally fast for me, not an especially quick reader). I wish it were a little more accessible but the gore would make it difficult for some. But if that's not your problem, I cannot recommend this fantastic novel enough.