Ever since I tore through this fast-paced post-apocalyptic story, a little corner of my mind has been pondering the horror of living in a world where you can't open your eyes outside. We never really know what the "monster" is, but the true terror comes from the many unknowns in the story. Blindfolded outside, the characters imagine being (or perhaps really are) surrounded by creatures who, if seen, make you go violently insane. The children in the story have never seen the outdoors, and horrible necessity has forced their mother to do nothing but train them from infancy to be obedient, keep their eyes closed, and rely on their hearing over their vision. An excellent psychological suspense that would have felt right at home as one of the classic Twilight Zone stories.