The stag do/bachelor party/enterrement de vie de garçon (“burial of the life as a boy” – if you want to get French about it) has changed beyond recognition since the days when our parents’ generation got married. It began as a few drinks in the local bar the night before the wedding. Now it’s a full-scale, alcohol-fuelled annexation of Eastern Europe/Las Vegas. In fancy dress.

This year, more than two million weddings are predicted to take place in the US and 200,000 in the UK. It’s the reason why your next free weekend is in October. And in the run-up to the summer, a mammalian mass migration, second only to that of the caribou, sweeps across the Western world. Stag season is upon us once more.

How did we get here? The origins of the stag do can be traced back to ancient Sparta, where soldiers would hold a banquet to honour a groom’s final night as a free man. Today, it is a different kind of endurance event – one you’re not necessarily proud to complete (also, the Spartan helmet is now made from a plastic composite).

First, some introductions. Below, some of the dudes clogging up that WhatsApp chat. For one hazy/hazing weekend, you’ll be closer than family. Come the wedding, you’ll likely struggle to remember their names.

It was supposed to be a gentle distillery tour followed by dinner and home by 10.00pm… Only, who booked the bored-looking adult entertainer? That would be this guy, a fun-enforcement agent whose only purpose is to make sure everyone has a good time, whether they like it or not. At the first rumbles of dissidence, he herds you all into a club so loud you have to communicate via strobe-lit sign language. Eyeing up an escape route? He magically appears with a tray of peyote-laced shots and handcuffs. This cult leader is a free-form spirit, a shadowy shapeshifter who only comes into physical being when the celestial bodies align – or if a pint glass is less than three-quarters full and doesn’t have a cocktail umbrella sticking out of it. In the real world, he doesn’t even exist.

You can begrudgingly accept the T-shirt with “Wolf Pack ’25” emblazoned on the back. In the context of a municipal airport, it at least gives fellow passengers a heads-up on who to swerve. And you have only yourself to blame for the smutty nickname – you suggested it when the emails went around four months ago. But there’s always one who wants to push the envelope. He’s turned up dressed as a cheerleader, with a two-man camel outfit in his hand luggage, and he’s reserved the back half for you. His suitcase contains more costume changes than the average Beyoncé concert, including all manner of “hilarious” inflatables, a mankini for the groom and a water pistol to be filled with duty-free vodka. Even before take-off, he has the groom gamely sporting a 1960s air hostess outfit, pointing out the emergency exits. Take note: you might want to make use of one.

Like Bruce Banner when he gets angry, an amazing transformation takes place the moment this man enters the stag-do arena. Usually a mild-mannered office drone with three children under the age of seven and a job that takes 10 long minutes to explain, by the second lap of the go-kart track, he thinks he’s Ayrton Senna in the 1985 Portuguese Grand Prix. He’s the shirtless own-brand John Rambo still running around the Laser Quest park gunning down tweens while everyone else is back in the bus. He bellowed a word-perfect “Like A Prayer” in the karaoke booth, finishing with a mic-drop into a puddle of… what is that? He’s somehow already at the next bar with a drink for everybody in the room, including the local dog walker quietly reading the paper in the corner. He’s got the waitress’ phone number, suspiciously missing a couple of digits. He’s fallen asleep, slumped face-first into his rogan josh. It is 7.19pm.

He was the first person to book his flights and kept awkwardly chipping in – always with too many emojis – on the group chat. He’s the bride’s brother’s best mate’s cousin, or something. He seems to know Steve. Then again, Steve has since gone home. Was he dating Jeremy’s sister? He’s the neighbour the best man got to feed his cat that time he went snowboarding in Canada. But now the best man is shrink-wrapped to a lamppost, so he’s stood on his own at the bar, looking a bit lost. He was at that house party in 2018, when Chris threw up in the fish tank. He wore the orange sweater. Hang on, isn’t he our minibus driver? And isn’t that your beer he’s drinking?

He only planned to show his face on the first night to keep the bride happy, but it’s day two and that face looks haunted. He spent the first few hours nursing an ale, blending in (with the pub’s carpet, mostly). Then he came unstuck in the drinking game – the one where it keeps on changing direction and you have to neck a shot of tequila if you forget to put your left hand to your right ear; two if you don’t address the person three seats away as “Captain Fandango” – and had to spend 40 minutes speaking like a pirate. Even when he phoned home, again, to check that Lauren got to gymnastics OK (she did). Someone, we won’t mention who, scrawled “Tosspot” on his forehead in permanent marker after he passed out the night before and his skin looks raw where he scrubbed too hard trying to get it off. At the wedding weeks later, when you go to introduce him to your partner, “Tosspot” is all that springs to mind.