I absolutely love stories about historical investigations, hunting down clues, finding long lost secrets, deep academics, and secret societies. I need more. The chunkier the better! And the more deep thinking I need to do, the better. I want good twists that make me want to reread to find the clues that I missed. If it gets dark, great!
My favorites have been The Historian, The Cartographers, and the Robert Langdon books.
by Imagination_Priory89