The Secret History - by Donna Tartt

Under the influence of their charismatic classics professor, a group of clever, eccentric misfits at an elite New England college discover a way of thinking and living that is a world away from the humdrum existence of their contemporaries. But when they go beyond the boundaries of normal morality their lives are changed profoundly and forever, and they discover how hard it can be to truly live and how easy it is to kill.