The sun is not a god. It is an executioner.

For ten thousand years, the Red King has reigned in the absolute silence of the Honduran underworld. He is the last of his kind—a prehistoric species of celestial navigators driven into the lightless depths of the Merendón by a sun that turned predatory. They are the Camazotz: architects of the night, masters of resonance, and the hidden gardeners of human civilization.

But the "Permanent Dark" is failing.

As the sixteenth century dawns, the sun’s fire begins to breach the obsidian halls of the city, and the weight of the mountain threatens to crush the memory of a race that has forgotten how to be born. Into this dying kingdom stumbles K’inich, a disgraced Mayan scribe fleeing a war on the surface. He is not captured for food, but for his hands.

The Red King offers a terrifying bargain: K’inich will be given the "Marrow" of the ancients to survive the crushing deep, provided he records the true history of the world before the light turns the last of the King’s kin to ash.

From the frozen Archive of the Wingless Queen to the blood-soaked vaults of the Great Hunger, K’inich undergoes a harrowing biological transformation. He must survive the "Red Tape" of human bureaucracy, the blades of the Jaguar Priests, and a subterranean flood that threatens to drown the very concept of time.

In a race against extinction, a man of the sun must become the Echo of the Shadow. Because when the last god falls, who will be left to tell the stars that we were here?