When Elsa's father is killed in a tornado, all she wants is to escape - from New York, her job, her boyfriend - to somewhere new, anonymous, set apart. For some years she has been haunted by a sight once seen from an aeroplane - a tiny, isolated settlement called Thunderstown. Thunderstown has received many a pilgrim, and young Elsa becomes its latest - drawn to this weather-ravaged backwater, this place rendered otherworldly by the superstitions of its denizens. In Thunderstown, they say, the weather can come to life and when Elsa meets Finn Munro, an outcast living in the mountains above the town, she wonders whether she has witnessed just that. For Finn has an incredible secret - he has a thunderstorm inside of him. Not everyone in town wants happiness for Elsa and Finn.