I was very recently on a tube, if you can believe it.
My exact whereabouts escape me but it was perhaps the Victoria line at Green Park. I was changing for another line.
Anyway, so I'm on this train, right. It's about 7pm-ish and it's reasonably busy. Most of the seats are taken, a good few people are standing. I am one of the latter.
I'm by a double door, holding on to the vertical pole that separates the seating bit from the standing bit. You know, the bit with the glass partition. The double door opposite me is about to open at the next stop.
The following takes place over the course of about three seconds.
As the train comes to a halt I let go of the pole and lose my balance ever so slightly, leaning acutely towards the seating area. It's no problem for a pro like me and I gracefully shift my centre of gravity to arc myself back into position.
So now my left leg is probably an inch away from the pole. I'm facing toward the door that's about to open, and my left arm is straight out to my side, slightly behind me. It's bending back towards me, directly above the man who's sitting at the first seat.
Except he's not sitting down any more. He's stood up, and my open hand connects with flesh. It happens behind me, but there's no mistaking what's occurred.
I've slapped him in the face.
Maybe it wasn't quite a slap, or a smack if you will, but it definitely wasn't a gentle caress either. It's a substantial blow and if it had happened to me I'd be pretty angry.
I turn round and another thing becomes clear - I'm going to have to break the "no talking on the tube" rule and apologise to this guy, bloody well immediately.
I apologise profusely - my stunned, gawping, guilty face doing more to placate the guy than any words I could muster. My hand gently rests on his right bicep as a show of peace.
The chap is probably in his late 30s, stubbly, average height, dressed sort of smart casual.
He is entirely unfazed and smiles politely at me.
"That's alright!" He says cheerily.
I cannot believe it. He is totally okay with what's happened. It's nothing to him.
I look at him a little longer and it's clear he's finished with our interaction, content to go about his day. So I turn around to face the door again, and after a couple more seconds of wondering how I've got away with it, they finally open.
At this point I become extremely suspicious. I dart away from the situation, looking over my shoulder, expecting him to appear. Maybe he's a bit like Rory Breaker from Lock Stock and Two Smoking Barrels - heading above ground to call me an ambulance before returning to my platform to rip out one of those metal benches and smash me to death with it.
Thankfully I make it to the Piccadilly line unscathed.