Gen has lived his whole life in a society ruled by order and obedience. Now he and Duff want to make a break for freedom. But do they dare enter the forbidden tunnels ... and defy the Guardian who controls their entire world?
Another entry in the "children's underground dystopia" microgenre. So far I am aware of Journey Outside (1969), Shadow of the Gloom-World (1977), The City of Ember (2003), and now Guardian of the Dark (1992). It seems the world can only sustain one each decade or so. There may be a couple undiscovered around the 50s, 80s and the 10s.
Very short, and doesn't do much to set itself apart from the others. You can probably guess what happens. The ending is slightly bittersweet: