Spanish/84 min./1975
Someone who wears a blue mask, is squat and has giant hands are killing people and stealing jewelry and money. The witnesses are afraid to talk, despite the detective understands that the clues point to his friend Blue Demon. This is actually an evil plan hatched by the Count and a fighter called ' The Cossack ', taking revenge on Blue. In both the real Blue Demon campaign starts with his secretary and a detective to unravel the mystery.