That morning she indulged herself in a large latte and a blueberry muffin at the Caffè Nero on the ground floor of the Oxo Tower. Joggers flashed by, and already the tourists were holding up their mobiles for selfies along on the waterfront. Two excited young women, who looked as if they were preparing for a modeling session, sat at the next table and discussed angles and locations with their photographer. With her black hair tied back in a loose chignon, accenting her high cheekbones, and her dark eyes, olive complexion and slender but shapely figure, Zelda herself might have been taken for a model, though her uniform of jeans, white open-neck shirt and kidskin jacket were hardly the apex of haute couture. She did notice the photographer glancing at her out of the corner of his eye, as if appraising her, from time to time. It made her feel a little uncomfortable but didn’t bring on a tsunami.

Foyles was in full swing when Zelda arrived, a huge, bright book emporium with a wonderful sense of natural light and space. There were the requisite displays of notebooks and gift items by the ground floor cash registers, but beyond stood a wall of recent titles facing out toward the reader. For a few moments, Zelda just stood there, overwhelmed, reading titles but not really taking them in. On her previous visits she had always been either browsing or searching for a specific title, but this time she had no idea where to begin. She had vaguely worked out how she would approach Keane’s girlfriend, but not how she would find her in the first place. At least she wasn’t working the ground floor tills, so that was a start. These things all seemed so easy in movies, but in real life they were a different matter. She didn’t think she looked threatening or dangerous, so she hoped that the people she talked to would trust her and not feel they needed to hide the truth or call the police.

She decided that the best thing to do would be to check out all five floors first, and if there was no sign of her there, she would start showing the photograph around to members of the staff. She was nervous about that, as she had no more of an explanation for it now than she had the previous evening in the restaurant. No doubt she would think of something.

And so she began her search, walking each floor, checking the faces of anyone at an information desk, carrying or stacking piles of books, adjusting shelf displays or talking to customers, until she arrived at the gallery and cafe on the fifth floor. The woman serving behind the counter there definitely wasn’t the one she was looking for; nor were any of the people sitting at a table enjoying a coffee break.