Centuries after a devastating catastrophe, humanity clings to survival deep within The Undercroft, a vast underground city. When young scavenger Elara unearths a device hinting at a vibrant, living surface, her discovery shatters everything she knows. But the truth is far more terrifying: the "surface" is a cosmic lure from an interdimensional entity known as The Shroud. Now, with humanity's very existence hanging in the balance, Elara must confront a harrowing choice: remain sealed in their subterranean prison, or risk cosmic annihilation for a freedom that might be a beautiful lie.