The first rule about a black woman’s hair is you don’t talk about a black woman’s hair. And the second rule is you don’t ever touch a black woman’s hair without getting written permission first.

The general public have a warped view of the speed at which an investigation proceeds. They like to imagine tense conversations going on behind the venetian blinds and unshaven, but ruggedly handsome, detectives working themselves with single-minded devotion into the bottle and marital breakdown. The truth is that at the end of the day, unless you've generated some sort of lead, you go home and get on with the important things in life - like drinking and sleeping, and if you're lucky, a relationship with the gender and sexual orientation of your choice.

When you're a boy your life can be measured out as a series of uncomfortable conversations reluctantly initiated by adults in an effort to tell you things that you either already know or really don't want to know.

Carved above the lintel were the words SCIENTIA POTESTAS EST. Science points east, I wondered? Science is portentous, yes? Science protests too much. Scientific potatoes rule. Had I stumbled on the lair of dangerous plant geneticists?

...good-Samaritanism in London is considered an extreme sport - like base-jumping or crocodile-wrestling.

Not being invited in is one of the boxes on the “suspicious behavior” bingo form that every copper carries around in their head along with “stupidly overpowerful dog” and being too quick to supply an alibi. Fill all the boxes and you too could win an all-­expenses-paid visit to your local police station.

Being a seasoned Londoner, Martin gave the body the "London once-over" - a quick glance to determine whether this was a drunk, a crazy or a human being in distress. The fact that it was entirely possible for someone to be all three simultaneously is why good-Samaritanism in London is considered an extreme sport - like BASE jumping or crocodile wrestling.