“[Patricia Highsmith] was overwhelmed by sensory stimulation - there were too many people and too much noise and she just could not handle the supermarket. She continually jumped, afraid that someone might recognise or touch her. She could not make the simplest of decisions - which type of bread did she want, or what kind of salami? I tried to do the shopping as quickly as possible, but at the check-out she started to panic. She took out her wallet, knocked off her glasses, dropped the money on the floor, stuff was going all over the place.”