A world at the bottom of all worlds, in which it is difficult for people to survive. Constant cold, natural disasters, hunger, constant darkness, and all this makes it impossible to live in such a place. The main character named Arlo lives with his grandfather in a cave. His life consists of extracting food roots, which are the only food in their world. Trying to survive, Arlo suffers from poor health that prevents him from being a full-fledged, energetic guy. He has heart and lung problems that make his life even more difficult. And so day by day, Arlo's life does not change in any way. Even though the people of this world around him are constantly trying to make a difference. After all, everyone has hope, and that hope is a high mountain called - The Great Horror. This mountain is right in the middle of their world, towering above everyone and having no end. And the goal of every inhabitant of this forgotten world is to climb this mountain, because at its very top is a portal that leads to a better world. But to reach the top one must be strong and ruthless. After all, no one has ever returned from there alive and no one has ever reached the top. After all, it's not just a mountain, but a whole house for multiple worlds in which danger lurks. One day Arlo gets the opportunity to be part of the team that must travel to the top of this mountain. Believing he must not miss this opportunity and despite his failing health he is sent to the preparatory camp headed by the fiercest and strongest of all soldiers, Bannard. Being part of a team made up of strong people is not easy. After all, in this place no one helps anyone and certainly no one loves anyone. Arlo will have to hide the fact that he has poor health. But there is no turning back. After all, he wants to achieve a better world and he is desperately in love with his teacher, Bannard.