A teenaged boy named Thomas awakens in a rickety elevator bearing food and supplies to the surface. He's greeted by a group of other boys who are already there---and has no memory of who he is. The senior boys explain that they all work together to survive in this strange environment. Their area is completely surrounded by massive walls, which he soon learns is part of a huge, ever changing maze. There's a small number of them who explore this--and they're aware there are these hideous monsters that prowl about. After Thomas becomes one of these runners he, and a few others, manage to explore further on and find an end to the maze. But why has it been constructed in the first place and why were they selected as participants?
Basically, THE MAZE RUNNER is LORD OF THE FLIES crossed with HUNGER GAMES. I must say I found this more engaging than HUNGER GAMES as it's a bit more dire and apocalyptic. Recommended.