Milliken and Mae have never left The Trench - it's all they've ever known. They were born in The Trench, and they'll die there, just like all their people do. The two girls, eight and eleven, are a part of The Trenchfolk, a sprawling settlement of people living inside the massive ice walls of a vast, seemingly endless frozen trench carved into the surface of an otherwise icy wasteland. The Trenchfolk survive in this hostile world by following The Three Testaments of The Trench - golden rules repeated like a mantra from birth to death.. 1. YOU MUST NEVER LEAVE THE TRENCH. 2. THE TRENCH PROVIDES. 3. THE TRENCH IS ENDLESS.