Can hypnotism really work?

Yes, if you are speaking of suggestibility. Hypnosis addresses the subconscious, so be careful what you don't think you think.

Hypnotism works best on people who are prepared to be hypnotised, and people who are susceptible to suggestions. Rebellious or obstinate people are more difficult to be put under control. Yes, it is kind of creepy. I witnessed one session, organised by my friends. The 'victim' spilled out his secrets under hypnosis. Later on he asked us not to talk about his secrets to other people.

I've never been to hypnosis session or magician that performs this, but I've heard from friends that have and they say it really does work. Kind of creepy if you ask me.