My dad was a fairy," said Zach. "And by that I don't mean he dressed well and enjoyed musical theatre.

On the plus side, there were no rioters in sight but on the minus side this was probably because everywhere I looked was on fire.

If you just warn people, they often simply ignore you. But if you ask them a question, then they have to think about it. And once they start to think about the consequences, they almost always calm down. Unless they're drunk, of course. Or stoned. Or aged between fourteen and twenty-one. Or Glaswegian.

Coffee arrived and the espresso was excellent, like an aromatic electric fence.

If you find yourself talking to the police, my advice is to stay calm but look guilty; it's your safest bet.

My dad was a fairy," said Zach. "And by that I don't mean he dressed well and enjoyed musical theatre.

For a terrifying moment I thought he was going to hug me, but fortunately we both remembered we were English just in time. Still, it was a close call.