"The story quite simply follows ‘Jack’ as he watches Mary and follows her around Whitechapel. He watches her with customers and eventually follows her home to commit his most atrocious crime."
Difficult to judge on such a short clip, but it looked OK except that Jack's shoes looked rather polished!
If I might make a suggestion, do you really need those special effects? It's possible that Jack himself couldn't see very clearly what he was doing. Why not have auditory horror instead - squelching, rustling and creaking noises might be quite effective in themselves.