When John Constantine is asked by Commissioner Jim Gordon to investigate a young girl in Arkham Asylum who is showing off strange abilities, he finds the girl is simply just too powerful in mystic arts, and does not know how to control her abilities. Her name is Zatanna. John soon agrees to train the girl in the mystic arts, taking her to become his student. At the same time, however, an ancient woman named Pandora frees the Seven Deadly Sins from their prison, becoming their host. Knowing this threat is too big for just he and Zatanna, John enlist the help of other magical beings, forming together the Justice League Dark.
