prisoners are trapped in chains behind a rock, facing a wall. There is a fire behind the rock, illuminating the wall, and men walk across the fire creating shadows. The shadows are all the men know, and believe them to be reality. However one day, a prisoner escapes from the chains and moves out of the cave in a painful journey to the bright outside. Once outside, his eyes are not adjusted and it is very bright, so he starts by looking at shadows of things, to slowly build up his vision, to the point where he can finally look at the sun and see the world clearly. He goes back to the cave to free his fellow prisoners, but they don't believe him and kill him.