Watch FMovies. Mystic Demon Killer is a Action/thriller/Spy feature film. Our darkest secret Operation D.E.M.O.N. has turned into our worst fear. MI6 agent Julie Morton with her special abilities is trying to find out the truth, Paul Hockley handles agents sent to this part of Wales (UK), Paul is EX Special Forces with a dark past. They both take on the hardest mission of their lives and find they are being helped by a masked warrior.