Jonathan Kellerman. The victim (№ 365268)

Notice, waddling on a dark city street eighty years old, and your vital signs - blood pressure, pulse, respiratory rate - remain the same. But replacing the old girl to a strong young man, with a casual look going to meet you, and the sympathetic nervous system switches into a higher gear. Of course, this psychological profiling is, of course, imperfect. Coming closer to the old woman, you see a guy disguised as a woman, and snatches of "trunk". But for the most part things are what they seem, and we all rely on it.
Try to live somehow, and see where it gets you.