I found myself unwittingly under an experienced tester in yet another experiment of a government organization. For them, I am just a criminal whom they would not be sorry to lose by sacrificing him to science. They take me behind the steel door of an abandoned building and close it, leaving me alone with the backpack given to me, which contains a supply of food for two days, two large flashlights and several dozen small ones, which I was instructed to leave on each flight of stairs passed. Behind this door is a staircase leading down. Every twenty steps there is a small staircase for a 180 degree turn to the next landing. But my flashlight only shines at a distance of ten steps, which is visually impossible! Something is clearly preventing the light from illuminating the stairs. I stick the first of dozens of flashlights to the wall and hear the noise of a walkie-talkie. The explorers demand to continue their descent down these concrete steps into this strange darkness! Okay... I have no other choice, I need to go down further.