Lindsay pulled up outside her flat. “But this is beautiful,” Cordelia exclaimed. “I didn’t know Glasgow was like this!” She gestured in the sodium-lit darkness at the crescent of trees outside Lindsay’s door, at the Botanic Gardens and the River Kelvin beyond, at the newly sandblasted yellow sandstone tenements elegant under their dramatic lighting.

“Most people don’t,” Lindsay replied defensively as she led the way upstairs. “We’ve also got eighteen parks, some of the finest art collections in the world, terrific architecture, and Tennents lager. It’s not all high-rise flats, gap sites, and vandals. But don’t get me started on my hobby horse. Come on in and have a drink and something to eat.”

Lindsay lit the gas fire in the living-room and poured them both a drink. She said, “Now, come through to the kitchen with me while I get some dinner together and tell me exactly what you know.”

As Lindsay put together a quick chicken curry, Cordelia spoke, pacing up and down the kitchen floor. “The first I knew about it was when the phone rang this afternoon. It was Paddy. She used her one permitted phone call to ring me because she knows I have a good solicitor and she wanted either her or someone local recommended by her. She wasn’t able to tell me much except that she’d been arrested and charged, and that somehow the police had found out she had some sort of motive.

“So I called my solicitor, who put me on to a firm in Manchester, who got someone out there right away. It’s a very bright-sounding young woman called Gillian Markham who specializes in criminal work. I’d just got all that organized, plus phoning Paddy’s parents to break the bad news, when Pamela Overton rang.

“She told me they’d had Paddy in for questioning for most of last night. Obviously, she doesn’t know all the details of why they’ve arrested Paddy, but she did tell me this much. You see, no one saw or heard anything of Lorna after Paddy had left her. And now they’ve got a couple of other bits of evidence, which, as far as they’re concerned, tie the murder to Paddy. They have statements from several people, saying Paddy was hanging around in the music department for ages for no apparent reason. And the toggle on the garrote comes from Paddy’s own duffel coat. It normally hangs in the cloakroom just outside her rooms.”

“How can they be sure?”

“It’s got special horn toggles, not ordinary wooden ones.”