Despite The Seven Deadly Sins' valiant efforts, the Demon Lord has returned--and this time, he's taken Meliodas's brother, Zeldris, as his vessel. In order to save Zeldris, Meliodas and Elizabeth head to Lake Salisbury to face the revived Demon Lord head-on. But the Demon Lord isn't the only adversary The Seven Deadly Sins are up against, and soon enough, they have their hands full when an army of Indura set their sights on Britannia!