Kayden Bos has fifteen years. He’s an excellent student, and also a wonderful artist. Lately he’s been wandering around the city alone, lost in his thoughts more and more often. Friends and family notice that he’s become somehow confused and contemplative. Kayden draws a lot—drawing something too strange and incomprehensible. And he also feels like a classmate wants to kill him… At the same time, Kayden is traveling aboard a huge ship. His mission is to obtain untold treasures in the Challenger Abyss. But in the real world, the Challenger Abyss is an abyss of madness—one that Kayden sinks into deeper and deeper every day.