An alarming moment

I’ve wondered from time to time, as one does when travelling on the Underground, what actually happens when you pull the emergency alarm. Today I found out. I was sitting in the middle of a London-bound train at Harrow on the Hill when I noticed a young woman, who had just boarded, moving in some agitation close to where I was sitting. The doors had closed and we were moving. She spun around once or twice then pulled down the lever. The train stopped almost at once, with most of the carriages still by the platform.
Someone asked “What’s the emergency?” and the woman said “My bag!” Evidently she had left it behind. Not really an emergency but maybe justified. Anyway, the doors were tight shut, there was no evidence of either the driver coming to investigate or any station staff doing anything so there we sat for a moment while she continued to dart about, knowing that her bag was on the platform somewhere just out of reach.
After a moment the driver made an announcement over the loudspeaker that the emergency alarm had gone off, and a bloke on the platform came up waving a handbag. Much relief from the owner, but the doors were still closed. He tried to cram it through the little window just where I was sitting. It was far too big. I suggested he speak to the driver. I don’t think he heard, or understood, so we continued to sit there for a while, until after several minutes the driver made his way into the carriage, turned off the alarm that was pointlessly bleeping all the time and opened the doors so that handbag and wearer could be reunited.
I’m glad it was not a real emergency. To be stuck in the carriage, with no way out and no way of communicating with the driver, would not be pleasant. I have always liked sitting at the very front of a train and now I have a cast-iron reason for so doing.