The District was a warren of lead-shielded, armored bunkers: of laboratories, in other words. Each scientist lurked behind reinforced walls that protected their laboratories from the experiments next door, and which might just protect the laboratories next door from what was going on inside. But their defenses weren’t perfect. Billowing clouds of fumes often bellied out over the rooftops; there was a nightly light show, with unidentifiable rays shooting out into the clouds — to what effect, no one outside the District could say — and there was also the constant din of construction, since so many laboratories suddenly became steaming craters and were, almost immediately, rebuilt for their new occupants. There was a tremendous amount of turnover in there.