A hyperdimensional suspense thriller that will challenge your limits!! A boy, deprived from all memory, found himself trapped in a mysterious world. He soon found out that this was a world of death, a world where you need to risk your life time after time and challenge yourself. Solve the riddles to escape the rooms of death! Kazuma, a young man who has lost all his memories, finds himself in a strange room with five other youngsters when he wake up. In these rooms, riddles spring up one after another, demanding they be solved within a given time limit- or face certain death! In this mental game of survival, what will be their fate?