At about 9.35 this morning, in the middle of rush hour, a photographer chats to a policeman at London Bridge station, towards the Tooley Street exit.
People dart everywhere, weaving their interesting mixture of good-naturedness, haste, anger, frustration, tiredness, nonchalance and confusion. It's busy, busy, busy.
The skinny photographer walks into a momentary space and plants a small inflatable globe, about the size of a honeydew melon, on the ground. He retreats and surveys the scene, bringing his viewfinder up to his eye. Commuters dodge around the mini world, confused. One guy accidentally kicks it off its spot on the floor.
The photographer jogs back to the toy, replacing it carefully in the centre of the melee. Turning, he jogs back to get a sense of perspective on the planned shot. The policeman looks on in amused silence.
Suddenly, a TfL man appears from nowhere, and whips the ball up from the floor, thrusting it in the photographer's chest. "I'm sorry, you can't just go putting that there," he says in classic jobsworth tones.
Moment, fun, photo, ruined.
I'd love to have stayed to see what happened. But I was running characteristically late for work.