In a land riven with plague, in the infamous Walled City, two families vie for control - the Medicis with their genius inventor Leonardo; the Lorraines with Galileo, the most brilliant alchemist of his generation.And when two star-crossed lovers, one from either house, threaten the status quo, a third, shadowy power - one that forever seems a step ahead of all of the familial warring - plots and schemes, and bides its time, ready for the moment to attack...