I don't like writing at home much," admits Shearman. "Home is a place for sleeping and eating and watching afternoon game shows on TV. There are too many distractions. So, years ago, I decided I'd only write first drafts in art galleries.

"And the best of them all is the National Gallery, in London, a pigeon's throw from Nelson's Column. I can walk around there with my notebook, thinking up stories - and if I get bored, there are lots of expensive pictures to look at. Perfect.

"A lot of those paintings, however, have angels in them. They're all over the place, wings raised, halos gleaming - perching on clouds, blowing trumpets, hovering around the Virgin Mary as if they're her strange naked childlike bodyguards. And I began to notice. That, whenever the writing is going well, the angels seemed happy, and would smile at me. And whenever the words weren't coming out right, when I felt sluggish, when I thought I'd rather take off and get myself a beer, they'd start to glare.

"I wrote this story in the National Gallery. Accompanied by a lot of glaring angels. Enjoy.