Willie’s drone sat in one corner. A red telltale winked several times in greeting as its camera eye swiveled to track the motion of their entrance. The upper ring of blades just under the comm dome began to whirl, buzzing as they did. The lower ring began its counter-rotation. As soon as both sets achieved speed, the drone lifted from the floor and folded its five-part landing gear together into a cone. The halfmeter-long cylinder, with its twin whirring necklaces of distortion, flitted through a window. Willie would be standing sentry while they investigated.