Last Wednesday, I was as at a very awkward Lee Mack gig, in Leicester. He would definitely remember it. After the first 30 mins, he had 3 'bad' hecklers, had to get his tour manager out into the audience twice, apparently, and the usherettes and security guard had to come out once. It was hilarious, but I wonder if the gig would've been as funny if that hadn't had happened. Other things happened, as well, by the way.
I saw Dara O'Briain a few weeks before that, and he was an expert at handling hecklers.
