While scrolling madly through incoming text and images on their mobile phones, the crush of teenage girls in the tube carriage shouted over the heads of all the other passengers. What vile behaviour, I thought.

I realised that I should have left my top-of-the-range iPhone securely zipped in the inside pocket of my jacket when one of the girls nudged another, then swiped it out of my hand. I tried to grab my phone back, but it had already been passed around several members of the gang and I had no way of knowing which teenager now held it.

I decided that my best strategy here was to impersonate an undercover police officer and demand the return of my iPhone. Remarkably this worked, and one of the gang slipped the phone into my hand at the next station. Although Gow was not my stop, I left the train here, keen to escape the packed carriage.

I caught the next train from the same platform at Gow station, forgetting to check its destination. Two hours later I ended up in Kent. Worse still, the phone returned to me turned out not to be my own, but a wide red flip phone from the 1990s.

I was desperate to call TPR and ask him to come and rescue me, but I didn’t know his number, nor that of KA who was in central London with him. I hoped that some men in a pub would help me out, but they had no sympathy for me. I should have memorised TPR’s number rather than relied on storing it in my iPhone contacts list.