Harry Potter, but all the magic obeys Murphy's Law. "Anything that can go wrong, will go wrong".
When depressed, disillusioned college student Quentin Coldwater gets accepted at a strange school where he learns magic is real, he is relieved that the problems that once plagued him are now solved. However, he quickly learns magic causes more problems than it solves.
This show puts the dark in dark fantasy, has a wonderful roster of supporting characters, and top-notch world-building.