Watch 123Movies. Cross the Hu-du-men - the demarcation between the back and front stage in Cantonese opera - and you leave yourself behind to totally absorb in your character. Lang Kim-sum is a charismatic Cantonese opera star who understands it's a point of no return once she crosses the Hu-du-men, on stage and in life. Respected by colleagues and friends, and about to retire, Lang has yet to face new, unexpected Hu-du-mens in domestic and professional life.