For a while nothing happened at all, and the only sounds on the landing were the Steward's ragged breathing and the faint tick of dust still falling from the turns above. Then the grey light in the open middle of the tower began to bend, the same way it had bent toward the black thread, and something came down through it slowly, standing upright in the empty air with nothing under its feet.
It stopped level with the landing, ten feet out over the drop, and looked at them.
