The night of my life on a lost weekend

Fortunately the painter I was meeting at the Natural History Museum turned out to be great fun. "Let's do the interview over a glass of wine," she suggested, explaining that she and her husband were staying for the weekend in London - leaving her son and friends to celebrate his 21st birthday at home.

The handsome man sitting patiently at the next table turned out to be her husband. Several glasses later they hatched a plan. "Why don't you join us for supper?" I was thrilled but anxious. "Won't I be in the way?" Nonsense, they insisted, I'd love their friends.

Before I knew it, they were driving me across town to gritty Vauxhall. "You could both be serial killers," I joked. "Hold that thought," they teased.

After a quick introduction to their (extremely tolerant) friends in Vauxhall, I was bundled into the back of a cavernous van. Seth and his wife run the Battersea mirror company, Overmantels, so they're used to ferrying strange cargo around. It's not often you get to buckle up in a Lloyd Loom chair in the back of a complete stranger's van. "Adjust Liz's blindfold, will you?" Seth roared - and we were off.

There's something liberating about inheriting someone else's social life in London. No fuss. No drama. They make all the decisions for you.

First we had drinks at the Prospect of Whitby pub ( a place I've never been in 20 years of living in London), opposite Wapping power station. Though I did slightly blanche when they took me down a narrow alley next to the pub to admire the Dickensian river bank. A hangman's noose loomed in the dark ahead. "She's getting nervous again," they joked.

Thanks to my new-found party, I got a late-night tour of the fashion show at Wapping power station (the curator Jules Wright is their old friend). Then Seth whisked us over to Dalston in the van for supper at their latest find - an amazingly cheap and brilliant Turkish restaurant.

I was dizzy with the absurdity of it. I was having the night of my life - with five brand new people. All strangers. It just shows what happens if you trust your instincts. When you're 20 everyone is far too uptight and self-conscious to leave their clique. But after 40 you're always hiring.

I would heartily recommend everyone has a Lost Weekend in London. It's good for us to be tourists in our own city. Chat up a group of strangers tomorrow. And just go with the flow. But do keep an eye out for the blindfold.

Tingle-Tangle - painter Roxana Halls's wonderful paintings on the theme of cabaret and female burlesque, upstairs at the National Theatre until 30 May.