Vera gave a bright little smile. ‘That’ll be one of the things the two of you have in common – the music.’ She turned to Kate. ‘My sergeant said you were a star at one time. What made you give it up?’

‘Oh, you know. Family commitments. Kids.’ Kate shook her head as if she was embarrassed to talk about it.

‘But I’m persuading her to rebuild her career.’ The man’s voice was earnest and it was almost as if he wanted Vera’s approval for the new venture. He stroked Kate’s hair, and the charge of intimacy made Vera feel awkward again. She said she’d take a second drink and some tea to her room.

The bedroom was well furnished and comfortable and looked out over the street. Vera sat at the window with her tea and her whisky, and when the glass was empty she topped it up from the bottle she kept in her bag. Also for emergencies, like the toothbrush and the clean knickers.

She thought about Margaret Krukowski, who had lived in this house for years. What had kept her in Mardle? Poverty, or a kind of lethargy? Perhaps she’d got used to the place and couldn’t face a change. And she’d liked this family, Vera decided. Liked watching the kids grow up and feeling that she was part of Kate Dewar’s life. A part of something. She might have been a self-contained woman, essentially private, but she hadn’t wanted to be completely alone. So what had Margaret made of Stuart Booth, who was closer in age to her than to Kate? Had she thought her life would change when Kate married?

Why had she been killed? Why now, on a snowy afternoon, when everyone was full of Christmas spirit? Why had she been stabbed? Vera was reminded of an old news story: a spy or a dissident stabbed with the end of an umbrella, the tip containing some lethal and secret poison. She’d thought at the time that the incident was ludicrous. There were easier ways to kill people, and this had smacked of little boys playing adventure games. Then she remembered George Enderby’s fantasy that Margaret Krukowski was a spy left over from the Cold War, and she thought she could see what had triggered his imagination. The exotic Eastern European name, of course, but also the sense that this was a private woman who carried secrets with her.

Share your secrets with me, Margaret Krukowski. Help me to find your killer.