You don’t get to be a senior investigating officer unless you have a degree in skepticism, an MA in distrust… — Ben Aaronovitch

Most people don’t see half of what’s in front of them. Your visual cortex does a shit load of imaging processing before the signal even gets to your brain, whose priorities are still checking the ancestral savannah for dangerous predators, edible berries and climbable trees. That’s why a sudden cat in the night can make you jump and some people when distracted, can walk right out in front of a bus. Your brain just isn’t interested in those large moving chunks of metal or the static heaps of brightly colored stuff that piles up in drifts around us. Never mind all that, says your brain, it’s those silent fur-covered merchants of death you’ve got to watch out for.

It’s a police mantra that all members of the public are guilty of something, but some members of the public are more guilty than others.

Dedication: This book is dedicated to all the people who get up and do something about it, whatever it is and however small the thing is they do.