It's been about six hours since the final whistle blew at the rugby, and things are starting to get messy.
A guy at the pub just near Millennium Stadium has lost his wedding ring and he's panicking, drunkenly fumbling around the floor, lifting people's legs up, reaching under tables. His mates aren't helping, they're just following along behind him chanting, "Tony's in trouble, Tony's in trouble."
It's that sort of evening. When you come to Cardiff to watch the Wallabies play, you sort of expect it.
My friends and I have to get the train back to London so we decide to call it a night, wandering back to the station to line up with all the other boozed-up punters in the hunt for transportation.
That's when we run into someone we know, an old mate from Brisbane days (who we'll call John for the sake of the story). He's been watching the game and drinking after it with a few people he knows, one of whom – we'll call him Mike – looks a bit the worse for wear.
Wait, that's not true: he's smashed. He's swaying on his feet, one eye half shut, slurring his words.
"Watch out for the train tracks," my friend says to him as he lurches along the platform.
"Mate," Mike slurs, "I live in London. I think I know about... train tracks."
With that he wanders off, into the crowd, in search of who knows what. We look over to John. "Will he be OK?"
"Yeah, he'll be right. Just let him go."
Except he's not all right. A few minutes later we all just happen to turn around at the same time and get to see Mike's accident unfold in slow-mo.
He's still stumbling along, and goes to walk around a few people standing just near the tracks. As he does it the group shifts slightly, knocking our man off balance.
He lurches, then crashes to the ground like a tree cut down, smacks his head on the concrete platform with a loud thunk, then rolls, and rolls, and finally topples off the side and onto the train tracks.
There's panic. A few of us lean over the side and grip his arms, pulling the dazed, bleeding guy up over the lip of the platform and to safety. He's in a bad way. A girl who says she's a nurse grabs some tissues, pressing them to Mike's head as we drag him over to bench and sit him down. Two policemen quickly arrive.
Mike's in shock, and so is John. He shakes his head. "He's s'posed to be going to a party in London tonight. It's not looking good!"
Mike was apparently OK in the end, but I didn't wait around to find out. My friends and I got on the next train, figuring there was nothing more we could do, while John stayed around to look after Mike.
They spent the night in a Cardiff hospital, the two of them, Mike being cared for and John just hanging around wondering where it all went wrong, how he ended up stuck in Wales, covered in blood and vomit, looking after his buddy when he should have been tucked up in bed in London.
Mates, eh? Sometimes you can't travel without them – other times you sort of wish they weren't there.
I've travelled with plenty of people who've gone off the rails a bit. Actually, it used to be my job to do it. As crew on European bus tours you get used to the passengers letting a bit looser than they really should.
I've had a gap-year-aged girl throw up all over me as I went to help her out of an Amsterdam bar and into a taxi to get her home to sleep it off. So that was the end of my night too.
I've had people do some disastrous things in their tents at night and then need to be shown how to clean it up the next morning. I've had passengers get drunk and lose their passports, or just lose their way altogether.
A couple wound up on drugs charges. Others went on a bottle-throwing rampage through a French campsite and got us banned forever.
Travelling with friends is fun and all - but sometimes, you can see the appeal of going solo.
Have you ever travelled with friends who've gone off the rails? Or had something terrible happen to them? Or who you've just gotten sick of?