Once upon a time, I exited at a tube station at the fringe of Central London. I noticed that many business cards were left at the telephone area inside the entrance of the station. That was perfect for a shy and adventurous person. I hardly knew any person but still I was afraid that I would ran into some friends in central London.
When I had the chance I went to the station again, arriving just after dark. I went to the telephone area to make a call, saving the embarrassment of entering a telephone box full of sleazy business cards.
With my head 12 o'clock dead straight ahead, I tried to move my eye balls as far sideways as possible, glancing at any number I could found. The woman who answered the call had a nice young voice, but laughed at me for not knowing where her street was. Most working girls there worked on that street.
Unlike other streets around, this one was completely dead and quiet right after dark. It was a normal side street, very roughly 100, 200 meters long and straight, with just enough space for parking at both sides. I remembered that I have to climb a flight of long stairs. The door was huge like that of a castle, and there was nothing at the door for cover. I was sure that the whole street could see me when I rang the doorbell.
Before that a more than 6-ft tall bobby walked pass me face to face, complete with imposing full winter uniform, helmet, and a cape. He walked slowly as if he was trying to help while I was looking for the right street number. I knew it was a deterrent and sarcasm of sort but I wasn't brave enough to turn back. I turned away from him, walked up the stairs as if nothing happened, pushed the doorbell and prayed that someone please open the door to save me from embarrassment.
On another such rare occasion, possibly at the same station or not, I used the same technique to spot and memorize a number. The place was crowded, and without the privacy of a phone booth, I was going to a quiet street corner to use my mobile. I pretended that the call at the public phone didn't get through, by pressing some buttons repeatedly in frustration. Unfortunately the button was a 9. I hanged up and walked away, but I could still hear that the dispatcher was asking the caller to response. The urgency got higher by the seconds as I was walking away.
ps After touring Soho via Google street view, I concluded that the flats with working girls are in the areas where street views are abruptly blocked off.