Italian action adventure co-written and directed by Mario Bava. When Viking forces are defeated and repelled from the shores of England in 748 AD, Erik (George Ardisson), the young son of the defeated Viking king, is left behind and raised by the English queen as her own son. Years later and now holding the title of Duke of Helford, Erik is forced to take up arms as England once again comes under attack from invading Viking forces, this time led by his brother Eron (Cameron Mitchell). The cast also includes Alice Kessler, Andrea Checchi and Ellen Kessler.