She often spent Saturday afternoons combing the antique clothing stalls in Camden Market for quixotically stylish bargains which, while they infringed no Service rules, certainly raised a few eyebrows. It was a bit like school, and Liz smiled as she remembered the grey pleated skirts which could be dragged down to regulation length in the classroom and then hiked to a bum-freezing six inches above the knee for the bus-ride home. A little fey to be fighting the same wars at thirty-four, perhaps, but something inside her still resisted being submerged by the gravity and secrecy of work at Thames House.

Intercepting her smile, a strap-hanging commuter looked her up and down. Avoiding his appreciative gaze, Liz ran a visual check on him in return, a process which was now second nature to her. He was dressed smartly, but with a subtly conservative fussiness which was not quite of the City. The upper slopes of academia, perhaps? No, the suit was hand-made. Medicine? The well-kept hands supported that idea, as did the benign but unmistakable arrogance of his appraisal. A consultant with a few years’ private practice and a dozen pliant nurses behind him, Liz decided, headed for one of the larger teaching hospitals. And next to him a goth-girl. Purple hair extensions, Sisters of Mercy T-shirt under the bondage jacket, pierced everything. A bit early in the day, though, for one of her tribe to be up and about. Probably works in a clothes shop or music store or… no, got you. The faint shiny ridge on the thumb where the scissors pressed. She was a hairdresser, spending her days transforming nice girls from the suburbs into Hammer Horror vampires.

Inclining her head, Liz once again touched her cheek to the silky scarlet nap of her scarf, enveloping herself in a faint scented miasma which brought Mark’s physical presence-his eyes and his mouth and his hair-rushing home to her. He had bought her the scent from Guerlain on the Champs Elysees (wildly unsuitable, needless to say) and the scarf from Dior on the Avenue Montaigne. He had paid cash, he later told her, so that there would be no paper trail. He had always had an unerring instinct for the tradecraft of adultery.