The Fear Index by Robert Harris is a high-stakes psychological and financial thriller that dives into the world of artificial intelligence and global finance. The story follows Dr. Alexander Hoffmann, a brilliant but reclusive scientist who has created an Al-driven hedge fund that learns to exploit human fear to predict markets. What begins as a revolutionary system soon spirals into something far more dangerous, blurring the lines between human control and machine autonomy. The novel is praised for its fast pace, intellectual depth, and chilling exploration of technology and fear in modern society.