Meghpur is a flooded megacity that runs on lightning. Every monsoon the storm tears the sky open, and Stormborn, creatures of rain and lightning, fall through. Asha, the fastest delivery Runner in the city, has twelve minutes to get insulin across the flooded bazaar. Then the power dies, something rises from the water, and a tiny Stormborn named Bijli needs her help. Now Stormline's Wardens are hunting Bijli, and Asha will have to outrun the storm itself.