While hunting for the elusive Sky Fish, Meliodas and Hawk discover a hidden spring that instantly carries them to the Sky Temple—a stunning realm perched above the clouds, home to beings known as Celestials. Yet Meliodas bears an uncanny resemblance to a notorious local outlaw named Solaad, leading him into imprisonment and ostracism. At the same time, the Sky Temple"s rulers gear up to protect Great Oshiro's seal—believed to contain a three‑thousand‑year‑old menace—from the sinister Six Knights of Black, demons intent on shattering it. The demon clan is unleashed and wreaks havoc across the land, forcing the remaining Seven Deadly Sins together with the Celestials to confront their evil adversaries. The conflict proceeds favorably until one of the Six Knights summons an "Indura of Retribution," a ferocious beast from the Demon Realm. With its immense might and malevolent force, the Seven Deadly Sins and Celestial allies must unite to vanquish this threat that endangers all of them in the face of looming catastrophe for survival of their world.
