Thorgal and Kriss manage to enter the city of Ogotai, the cruel god, thanks to the help of Commander Hog who leads a kind of rebellion against his sovereign. Our heroes discover then that the real purpose of their mission is not simply to steal the magical helmet of Ogotai but to kill him. Thorgal, as he flees, ends up discovering that Ogotai is his father, so he decides to find out more...