I had to sit in that window and smoke non stop for 6 hours.
Of course, Control knew I hated smoking. It was his sick joke to make it the signal.
I had all but lost my sense of smell when my contact finally appeared. He was slumped on a bench in the street below. He was quite motionless... this is generally seen as a bad sign in the spy game.
As I was thinking about the other bad signs... the floorboards creaked.
I had smoked 40 cigarettes that day, but I savoured that last one.