talkmagic.co.uk

You do sometimes stumble across the kind of spectator who sees all magic as a challenge and has no desire to be entertained.
It's always good to have a couple of effects that will shut them up. One that works for me is a bare handed, rolled-up sleeves lit cigarette vanish (no T-T used) which seems to flummox everyone.

If the person is disrupting a group who are otherwise enjoying your performance, I sometimes perform Paul Harris' Ultimate Rip Off and state:
"As this gentleman appears to be a very knowledgable magician, he will now restore the last piece for you all!"

When all the heads turn to him in anticipation, you can be certain he will shut up!