“Or, as you say, her. I suppose it is the twenty-first century, and if a girl wants to creep around hotels offing people, we should encourage her. But that aside, what do you actually intend to do?”

Liza had been trying not to think about this. And in a way it had been fairly easy, because in some ways, “How do I deal with this murderer I have definitely caught and I know is definitely guilty?” was a good problem to have. Of course, in other, potentially very dangerous ways, it wasn’t. “I’m not really sure. Your nephew does this kind of thing, doesn’t he? What does he do?”

“Cheats. He has a fellow at the yard does the difficult bits for him. He’s terribly clever is Dicky, but it turns out cleverness very seldom stands up in court. So what he’ll do is he’ll ring up this chap he knows and he’ll say, ‘Look here, old thing, I’m quite convinced that you want Mr So-and-so or Miss Whatchamacallit for this caper,’ and then his friend will deal with all the stuff with forensics and witnesses and everything, and that will be that.”

Rubbing her chin sceptically, Hanna said, “You realise you’re making it sound a bit like he just goes around fitting people up.”

Lady Tabitha shrugged. “Possibly, but it does him good to have a hobby.”

A lull entered the conversation, which Hanna filled by observing that the solid platinum poignard had been returned to the mantlepiece.

“Yes.” Lady Tabitha turned to admire it. “Looks rather handsome, doesn’t it? Although what the colonel thought he was going to do with the thing I don’t know. Still, I suppose a military man in a situation like this will get a kind of a foxhole mentality.”

That wasn’t something Liza had considered, and she couldn’t quite tell if it made him more suspect or less suspect. That had also brought them to the end of the topics they could talk about without getting into the more … accusatory questions. “And …” Liza hesitated. Sir Richard had, after all, been right in a way. Even if Liza wasn’t responsible for Vivien Ackroyd’s death, accusing her of two murders had helped precisely nobody and caused Liza and Hanna a whole lot of aggravation. As well, she tried not to remind herself, as making Mrs Ackroyd’s last hours before her murder needlessly stressful. “And,” she tried again, “is there … I’ve been told that you had a conversation with Mrs Ackroyd the morning she died.”

Lady Tabitha looked up, and any faith Liza may have had in her own ability to read people evaporated. There was a studied unflappability on Lady Tabitha’s face, a mix of hauteur and apathy. “Are you accusing me of something, dear?”