Since all I had to go on was the magical echo of one particular jazz tune, I figured it was time to find out precisely which of several hundred cover versions of “Body and Soul” it was. What I needed was a jazz expert so obsessed that the subject had consumed him to the point where he neglected his health, his marriage, and his own children.

It was time to go see my old man.

MUCH AS I love the Jag, it’s too conspicuous for everyday police work. So that day I was driving a battered silver ex–Metropolitan Police Ford Asbo that, despite my best efforts, smelled vaguely of old stakeouts and wet dog. I had it stashed up Romilly Street with my magic police business talisman in the window to ward off traffic wardens. I’d taken the Asbo to a friend of mine who’d tuned up its Volvo engine and gotten me a satisfactory bit of zip, which came in handy dodging the bendy buses on Tottenham Court Road as I drove north for Kentish Town.

Every Londoner has their manor—a collection of bits of the city where they feel comfortable. Where you live, or went to college, where you work or your sports club, that particular bit of the West End where you go drinking or, if you’re the police, the patrol area around your nick. If you’re a native-born Londoner—and contrary to what you’ve heard, we are the majority—then the strongest bit of your manor is where you grew up. There’s a particular kind of safety that comes from being on the streets where you went to school, had your first snog, or drink, or threw up your first chicken vindaloo. I grew up in Kentish Town, which as an area would count as a leafy suburb if it was leafier and more suburban. And if it had fewer council estates. One such is the Peckwater Estate, my ancestral seat, which had been built just as architects were coming to terms with the idea that proles might enjoy indoor plumbing and the occasional bath but before they realized that said proles might like to have more than one child per family. Perhaps they thought three bedrooms would only encourage breeding among the working class.

One advantage it did have was a courtyard that had been turned over to parking. There I found a clear bay between a Toyota Aygo and a battered secondhand Mercedes with a criminally mismatched side panel. I pulled in, got out, beeped the lock behind me, and walked away secure in the knowledge that because they knew me around here they weren’t going to jack my car. That’s what being on your manor is all about. Although, to be honest, I suspect the local roughnecks were much more scared of my mum than they were of me. The worst I could do was arrest them.