reporter: from the villainous plot of "the manchurian candidate" where a former prisoner of war the hypno tisedme an assassin -- >> do what you have been trained to do and kill the malaysian prime minister! >> reporter: to a modern spoof on that same premise in "zoo lander." hollywood hyperbole aside, doctors say hypnosis can be effective within limits, of course. >> the basic law of hypnosis is that you cannot make people do what they don't want to do. however, what they don't tell you is that we can affect the things that you want or desire. >> reporter: dr. daniel chew uses hypnosis in his practice to address anxiety orders, phobias, and depression in his patients. his employee daniela graciously agreeing to go under with our cameras rolling. she trying to stop smoking. >> there are several steps in hypnosis. the most important part is the induction part. that's where you try to get them to focus and relax. >> reporter: his tool, not a pocket watch, but just his voice. >> i w slowly inhale. three, two, one -- >> reporter: within moments, falls into a trance-like state. >> the next phase is c