Absolutely phenomenal. Pressfield gives a masterclass in historical fiction, not just managing to form the prose in a way you would imagine the Greeks to have actually sounded, thereby placing you that much firmer within the story world, but also giving a deep insight into the Spartan way of life and by extension, into the characters. The characters are what makes the book, perhaps even aside from the epic battles. Though most characters are similar, they all have their own conflicts and dreams, which are all lost in the battle that defines the book. This struggle, for family, country, brothers is far from unique in writing, but not often has it been written down so splendidly.