What happened to Meliodas? He no longer speaks, his face is impassive and he wears strange black marks on the body. Worse, he starts attacking enemies as allies without any distinction! To stop it, Helmram must resort to his magical power that concentrates the strength of dozens of Sacred Knights. Meliodas loses consciousness and Diane takes over: mad with rage to see his leader worshipped in this state, the giant makes a carnage and the Sacred Knights are forced to retreat! This fight leaves a bitter taste to the Deadly Sins who wonder if their leader is not a demon...