It was definitely the first time I'd ever popped out for a Chinese halfway through a play. But this was no ordinary play, this was Gatz, an eight-hour performance of The Great Gatsby in which every line, every last "he said" and "she said", of F Scott Fitzgerald's novel is read aloud on stage.
Going to see Gatz takes longer than the average working day. It starts at 2.30pm and ends at around 10.45pm, and in between there are 48,891 words. The performance itself is a little over six hours long. The rest of the time is taken up with intervals to give the audience time to eat and drink in order to "survive" the next act.
There's a 15-minute break after the two-hour first act (cup of Earl Grey), an hour and a half dinner break after the second (quick trip to Chinatown) and another 15-minute interval before the fourth and final act (double espresso).
For the theatre company, Elevator Repair Service, it's an extraordinary achievement. For the audience, it's a singular experience. It's also the only show to have ever given me jetlag. Emerging, blinking, at the halfway point, I was amazed to discover it was still light outside.
More striking was the way that the length of the show rewrote the rules of theatre etiquette. Many in the audience came dressed for comfort in hoodies and trainers, as if bedding in for a long-haul flight. One girl went a step further and brought her slippers along, watching the whole thing with her feet, encased in stripy, fluffy cosiness, slung up on the brass rail in front.
Friendships blossomed in the stalls as people shared their picnics of Diet Coke and sandwiches with slow-release energy fillings, swapped tips for avoiding DVT and even had their first dates over dinner in the second interval.
Endurance art – and I don't mean making it through to the final episode of The Voice – is having a moment. Last weekend Radio 4 broadcast a six-hour adaptation of Ulysses; last night Shakespeare's Globe staged a "midnight matinee" of Henry V which went on until 3am, with a post-show party until dawn; and last month Philip Glass' opera Einstein on the Beach had its UK premiere – all five hours.
Is bigger better? Perhaps these recessionary times demand bumper shows – more Bard for your buck. But why does the prospect of a four-hour Gone with the Wind in the West End make me run screaming for the hills while I'm the first to sign up for a glorified eight-hour bedtime story, of a book I've already read? The answer is in the experience. It's not enough to watch a play, you have to feel part of it, too. It's why the Globe, with its cagoules and Blitz spirit, remains eternally popular.
At the end of Gatz, the applause was as much a self-congratulatory pat on the back for the audience as it was praise for the actors. The stalls – strewn with energy drink cartons, banana skins and foil wrappers – looked like the aftermath of the London Marathon. The only thing missing was a medal: I survived Gatz! Had they been selling them in the foyer, the company could have made a killing.
* These are uncertain times but one can still cling to certain truths. Namely, the weather will always turn rainy just in time for Wimbledon fortnight and rock stars who say they are retiring are invariably lying. Lily Allen, pictured, who announced her "retirement" in 2009, aged 24, before embarking on a series of last-ever gigs in 2010, before making a three-part television documentary about her "normal life" in 2011 is now, in 2012, back where she started – in the studio.
This week, the singer hinted on Twitter that she was making music again. Meanwhile, her songs for a new Bridget Jones' Diary musical are being workshopped in the West End. Perhaps she thought she wanted to be sent off into the sunset with a carriage clock and an oversized farewell card but when she got there realised that she preferred the limelight after all.
Whatever her motivation, if she's this productive in her first retirement, I can't wait to see what she does in her inevitable second and third.