The Seven Deadly Sins travel to a remote land in search of the phantom ingredient "sky fish." Meliodas and Hawk end up at a "Sky Palace" that exists above the clouds, where all the residents have wings. Meliodas is mistaken for a boy who committed a crime and is thrown in prison. Meanwhile, the residents are preparing a ceremony for defense against a ferocious beast that awakens once every 3,000 years. But ...