The City of Ashfall is a young adult fantasy novel focusing on the journey of a mechanic called Rose Volta in a dystopian world where ash covers the sky and deadly rain forces most people indoors. Stuck in a city where the gap between the rich and the poor is insurmountable, Rose seeks to escape the ashen skylight. Her primary task is to maintain the System Manager of the hospital, Alba Rottame. However, Rose soon discovers that this machine is more than just pistons and wires.