Pre-war party in Poirot style

For some, fancy dress is a doddle. For others, myself included, the mere thought triggers serious

SS Atlantica's theme is Thirties ocean liner glamour, inspired by Agatha Christie's Poirot and films including Anything Goes.

"Our parties get mentioned on the vintage blogs, so we get quite a lot of vintage enthusiasts," Anne Kapranos, one of the organisers, tells me.

Immediately my mind is whirring, what will I wear?
An afternoon rummage in Stoke Newington's charity and vintage shops turns up key accessories — evening gloves, feathery hat, fan and a man's silk
tasselled scarf. Result.

Arriving at St Katharine Docks near Tower Hill, my boyfriend and I join the steady queue of girls in silk dresses and furs and men in tuxedos paying £15 to gain entry to Commodity Quay old trading house. There's a bar at one end, dance floor and stage at the other, tables, chairs, roulette and DJ decks in between and an adjoining room showing silent Charlie Chaplin movies.

Already the atmosphere is buzzing. Clutching our Monopoly money for the gambling tables, we head to the bar and order Screaming Hudson and Gin Fizz (both £6.50) cocktails.

There's a good vibe and a lot of amicable costume appraisal — everyone has made an effort. With many of the partygoers Prohibition veterans, feathered headdresses, satin gloves, pearls and red lippy are carried off with aplomb by the girls, while the guys sport black ties, trilbies, top hats, waistcoats and military uniforms.

Most of the crowd are in their late twenties and thirties with a scattering of older guests who are visiting from a classic yacht rally. Among others, I meet travel and beauty PRs, a graphic designer, a social worker, music students and even the London College of Fashion's Anglican priest.

En route to the dance floor, where a crowd is gathering for the cabaret singers, we stop at the roulette table where some of the yacht club silver foxes are accumulating chips. I look on, excited to lay my first bet, until my boyfriend gets us in trouble by jokingly pinching a chip. The croupier is not impressed.

Undeterred, I knock back the rest of my drink and drag my delinquent other half towards the decks where DJ duo Alex and Yu are playing their favourite jazz tunes. The debonair Alex, dressed in a tweed suit with accompanying monocle, tells me jazz and R&B are his passion and that he loves playing parties like Prohibition and SS Atlantica.
"You're playing for people who are living out a fantasy," he says. I glance around and see sparkly girls and dapper chaps all looking and feeling a little more fabulous than if they were just having a pint down their local pub. There is a real sense of fun and frivolity in the air.

The night is young and the cabaret is about to commence. Glamorous songstress Nova Skipp sings Gershwin's I Got Rhythm and Cole Porter's I've Got You Under My Skin with such infectious enthusiasm the toe-tapping crowd is growing.