As dissatisfaction with the old regime fermented into revolutionary upheaval in late-eighteenth century France, two architects cast off the decorative excesses of the Baroque and Rococo styles and sought out bold, new geometries. Hugh Aldersey-Williams tours the sublime and mostly unrealized designs of Étienne-Louis Boullée and Claude-Nicolas Ledoux, discovering utopian ideals crafted in cubes, spheres, and pyramids.