Welcome to Chilo, a planet with corrosive rain, crushing pressure, and deadly heat. Fortunately, fourteen-year-old Timas lives in one of the domed cities that float 100,000 feet above the surface, circling near the edge of a monstrous perpetual storm. Above the acidic clouds the temperature and pressure are normal. But to make a living, Timas like many other young men, is lowered to the surface in an armored suit to scavenge what he can.

Timas's life is turned upside down when a strange man crash lands on the city. The newcomer is fleeing an alien intelligence intent on invading the planet and discovering the secret hidden deep inside the perpetual storm—a secret that could lead to interplanetary war.

As the invaded cities fall silent one by one, Chilo's citizens must race against time to stop the enemy. And Timas will find out what kind of man he has become in the harsh conditions of Chilo's surface.