“…They were a very nasty couple. Bad type. Superstitious, like most crooks. She was the worst of the two, in my opinion. Tried to fix the job so’s it’d look as if the servants had done it. Do you recollect that, sir?”
“Yes,” said Alleyn slowly, “yes.”
“Mind,” said the constable warming a little, “I reckon if he hadn’t lost his nerve they’d have got away with it. No finger-printing in those days, you see. And you know how it’d be, sir. You don’t expect people of their class to commit murder.”
“No, you don’t. And with the weapons lying there beside these grooms or whatever they were, and so on, well the first thing anybody would have said was: ‘Here’s our birds.’ Not that there seemed to be anything like what you’d call an inquiry.’
“Not precisely,” said Alleyn.
“No, sir. No,” continued the constable, turning his back to the wind, “if Macbeth hadn’t got jumpy and mucked things up I reckon they’d have got away with it. They seemed to be well-liked people in the district. Some kind of royalty. Aristocratic like. Well, nobody suspects people of that class. That’s my point.”
–Ngaio Marsh, A Surfeit of Lampreys