David Gemmell is a legend (much like the title of one of his books). I know GRRM, Rothfuss and Brandon Sanderson are all the rage but Gemmell is a giant among men. His books are always action packed, intelligent and passionate, extra points also for them generally of being of medium lengths (300-600 pages). I love every one of his books that I have read but for the purpose of constructing my top 20 goodreads shelf I choose Lion of Macedon as being representative of his greatness.
Lion of Macedon is based on Greek mythology with Parmenion being the main protagonist, his development from a lowly half-Spartan into "The Death of Nations". The story is full of magic, strategies and tragedy, the complete story spans just two books, this one and the sequel
Dark Prince, which features a semi-possessed Alexander the Great. There is no question of reading just the first volume and abandoning the rest of the story, I can not imagine anybody wanting to do that.