Not everyone has the ability capacity capability to be hypnotized. It involves giving over control of yourself to someone else. Some will never be able to do that. But there are some who have no guards up at all and can be hypnotized very easily. Once "under" the hypnotist puts a suggestion in their minds and then a "magic" key which is usually a specific word that will unlock that door. You've seen the theatrical demonstrations of that on TV right? Some gal named Pat used to do a club act. She'd have folks get up on stage, put them under, plant a suggestion in their minds and then a trigger. She brought them out of it and then deftly employing the trigger word what were typical humans beings became chickens that were clucking or ducks squawking including arms and legs that cooperated. It was always hilarious apparently because the audience would laugh at the spectacle and the hapless folks had no clue what was happening. Then the hypnotist brought them out of it and would show them what they had been doing by rerunning the video tape. Fun was had by all? Not so much. I never liked to see folks being made fools of for other folks' entertainment. I still don't. The humiliated folks I imagine were embarrassed and not real happy although I don't know that. Never talked to one of them. Bottom line.
Folks who are amenable to being hypnotized will act accordingly. Remember THE MANCHURIAN CANDIDATE? They know not what they do or why. They just follow instructions embedded in their brains like automatons. Remind you of anything? Anyone?