“Yes, but that’s sort of …” Liza waved her hands. “There’s context there.”

“Tell me?” Hanna was doing her interested voice. She probably wasn’t; she’d only ever listened to Actual in a dutiful way, but it was nice she was making the effort. Of course, she might have only been making the effort to show up Ruby.

“Okay, so the thing about murder”—fighting the temptation to go into lecture mode, Liza began pacing—”is that nine times out of ten it’s really petty and really obvious. You get killed in your own house by somebody you know, usually by somebody you live with. Usually for a reason that’s incredibly boring and trivial.”

Ruby cocked her head to one side. “Like, they’ve realised that you were only sleeping with them in order to get your hands on the diamonds they stole from the Louvre? That kind of boring and trivial?”

“Or,” Hanna suggested, “like your wife pushing you off a balcony because she’s sick of you trying to get mobile phone reception at one in the morning?”

“More like the second one,” said Liza.

Ruby was sitting up now, almost as if she was actually paying attention. “Really? The thing with the diamonds has happened to me quite a lot.”

“Yeah, I don’t think your life is typical.” Liza tried to get her monologue back on track. “And I’m not ruling the it-was-the-wife option out, even if it is a bit …”

“Unsatisfying?” asked Ruby. “Tawdry? Unbecoming?”

“Sad, I was going to say.” And it was. Now she thought about it, Liza couldn’t quite shake how pointlessly sad she found it. “I’d rather believe Mr Ackroyd died because there’s a master criminal on the loose than because couples fight sometimes.”

Hanna winced. “For what it’s worth, I promise I won’t throw you off a balcony.”

“That’s the thing.” Liza turned to her wife. “You can’t promise that.”

The look in Hanna’s eyes was on the border between offended and incredulous. “I kind of think I can.”

Hoping that she wasn’t about to make herself sound like a total psychopath, Liza shook her head. “You can’t. I can’t either. People make mistakes. They snap, they shove somebody when they’re standing in the wrong place or lash out when they’re holding the wrong kind of knife.”

“There’s a right kind of knife?” asked Hanna.

Ruby grinned. “Dozens. If you’re very good, I’ll give you a demonstration.”

“Sorry,”—Hanna turned her attention back to the bed—”are you making flirty references to blood play while we’re discussing a man’s actual death?”

The grin didn’t seem to be going anywhere. “Ask your wife what I’m calling my autobiography.”