The Magician's Land - Lev Grossman (Book 3)

Quentin has been cast out of Fillory. Alone and adrift, he returns to Brakebills, the school of magic where it all began. But he can't hide from his past.

His new path will take him through a world of grey and uncertain magic, from Antarctica to theenchanted Neitherlands. But all roads lead back to Fillory. The magical barriers are failing and the realm faces destruction.

To save them, Quentin must unlock the secrets of magic and risk sacrificing everything.