When the mysterious Abyss, home to celestials and monsters, materializes on Earth, its inhabitants vie for human faith to sustain their powers. Amid benevolent celestials bestowing blessings for belief, malevolent ones seek dominion. Yeonseung Choi, an Earth protector against Abyssal perils, fixates on enhancing his skills. A celestial foresees him preventing Earth's engulfment by demonic celestials, forging a pact for his training as the prophesied hero. Can Yeonseung withstand the rigorous Abyssal trials and fulfill his destiny of rescuing Earth?