The thing about being a mystery writer, what marks a mystery writer out from a chick lit author or historical fiction writer, is that you always find a mystery in every situation.

I had been right: freedom smelled like ozone and thunderstorms and gunpowder all at once, like snow and bonfires and cut grass, it tasted like seawater and oranges.

I have always been caught by the pull of the unremarkable, by the easily missed, infinitely nourishing beauty of the mundane.

You forget what it was like. You'd swear on your life you never will, but year by year it falls away. How your temperature ran off the mercury, your heart galloped flat-out and never needed to rest, everything was pitched on the edge of shattering glass. How wanting something was like dying of thirst. How your skin was too fine to keep out any of the million things flooding by; every color boiled bright enough to scald you, any second of any day could send you soaring or rip you to bloody shreds.

That kind of friendship doesn't just materialize at the end of the rainbow one morning in a soft-focus Hollywood haze. For it to last this long, and at such close quarters, some serious work had gone into it. Ask any ice-skater or ballet dancer or show jumper, anyone who lives by beautiful moving things: nothing takes as much work as effortlessness.

Now death is uncool, old-fashioned. To my mind the defining characteristic of our era is spin, everything tailored to vanishing point by market research, brands and bands manufactured to precise specifications; we are so used to things transmuting into whatever we would like them to be that it comes as a profound outrage to encounter death, stubbornly unspinnable, only and immutably itself.

I like writing about big turning points, where professional and personal lives coalesce, where the boundaries are coming down, and you're faced with a set of choices which will change life forever.