Ruling from the island of Acacia, the emperor of the Known World has inherited an apparent peace and prosperity won by his ancestors generations ago. He's an intelligent man, a widower who dotes on his four children and it is this devotion that obliges him to hide a terrible secret from them: that their prosperity rests on the dark realities of trafficking in drugs and human lives. A man of integrity, he hopes that he might bring an end to this vile trade, but powerful forces stand in his way. And then an assassin strikes, a lone killer sent by the Mein, an ancient foe long ago exiled to the frozen north. Now the Mein have returned to take revenge on their old enemy and begin a series of brutal surprise assaults on Acacia. Mortally wounded, the emperor puts into play a plan that will allow his children to escape, to fulfil their destinies. And so begins a quest to avenge a father's death and restore an empire - this time on the basis of universal freedom...