Why are we drawn to certain cities? Perhaps because of a story read in childhood. Or a chance teenage meeting. Or maybe simply because the place touches us, embodying in its towers, tribes and history an aspect of our understanding of what it means to be human. Paris is about romantic love. Lourdes equates with devotion. New York means materialism. London is forever trendy.

Berlin is all about volatility. Its identity is based not on stability but on change. No other city has repeatedly been so powerful, and fallen so low. No other city has inspired so many artists and witnessed so many murders. It’s a capital city made up of villages. An island long adrift on a foreign sea. A city where history broods. Its legends, both real and imagined, stalk the streets: Lenin drinks at the same café as Bowie’s heroes, Wim Wender’s trench-coated angels wing above torch-lit Nazi processions, Speer conjures myths from the same canvas as Georg Grosz, Dietrich shops alongside Sally Bowles at Ka De We, le Carré’s George Smiley watches the packed trains leave for Auschwitz.

I’ve been coming to Berlin for thirty years, falling in and out of love with the brash, volatile city, moved again and again by its Walls and open doors. I first came here as a young assistant director on a David Bowie movie. I was fresh out of film school and Bowie, wanting to initiate me in the ways of the city, invited me and others to his favourite transvestite club, the Lützower Lampe. The club’s star, a sixty-year-old drag queen named Viola, sat on my knee and crooned German love songs in my ear. Over the next months we worked with Marlene Dietrich and, at the end of the shoot and Bowie’s Berlin sojourn, in a secluded restaurant in the Grunewald, he and I sang a duet (or, at least, two lines from ‘Good Golly Miss Molly’). Berlin was the place where I decided to become a writer, where I grew up.

Now I’ve made it my home again, like so many outsiders. I'm here researching and writing my new book, a biography of this city which has haunted and excited me for so many years, and will be published in 2013.