Just finished "The Private Memoirs And Confessions Of A Justified Sinner" by James Hogg. First published in the 1820s, I suppose it's of the gothic tradition though it departs from the genre in that it draws its horror from Calvanism rather than the Catholic world - a young man who believes he is one of God's elect befriends a mysterious stranger who grooms him into becoming a serial murderer of God's enemies. It's strikingly modern compared to other works of that era and is one of the finest books I've ever read.