Shale is in trouble - the creature-infested darkness know as the Roil is expanding, consuming the land and swallowing up whole cities.

Where once there were 12 metropolises, now only 4 remain, and their borders are being threatened by the growing cloud of darkness. The only way to hold back the darkness and the horrific creatures that inhabit it are the cities huge ice canons. But one by one the defenses are failing. And the Roil continues to grow.

With the land in chaos, it's up to a drug addict, an old man and a woman intent on revenge to try to save their city - and the world.