Many people hear “hypnosis” and immediately think of the scene from Star Wars with Obi Wan Kenobi’s famous line, “These are not the droids you are looking for.” The Jedi mind tricks in Star Wars only work on the weak minded. This is far from what real hypnosis is like, since it requires a good imagination and takes a good deal of concentration.
Most psychologists believe that any person of average (or above average) intelligence can be hypnotized, but in reality no hypnotist has a 100% success rate. Circumstances, and even the subject’s mood, can make it more difficult to be hypnotized.
This is why any professional show will start with the entire audience. That way, the hypnotist can see who the best subjects are. The most responsive people will be invited on stage. They will then be further hypnotized to identify who will be used for the remainder of the show. Often, hypnotists on TV will work with a hand full of subjects before filming to test how deeply they can be hypnotized.