‘Conchita, eh?’

‘Damn,’ said Herring. ‘You know about her?’

‘It's my business to know things,’ replied Spratt coolly, ‘I also know, for instance, that this mystery conforms to the Knox Convention.’

‘You mean—?’

‘Right,’ said Jack. ‘There's no chance of someone we've not mentioned turning out to have done it.’

‘That also rules us out as the detectives,’ added Mary, ‘and there must be clues.’

‘And in a story this short,’ continued Jack, ‘some of them might be in italics—so keep a sharp eye out.’

Jack turned back to Red Herring. ‘Who else was in the house at the time?’

Herring thought for a moment and counted the guests off on his fingers: ‘There was myself, Unshakeable Alibi, Cryptic Final Message, Least Likely Suspect, Overlooked Clue, and the butler, Flashback.’

Spratt thought for a moment. ‘Tell everyone to wait in the drawing room and we'll speak to them one by one without a lawyer present and in clear contravention of any accepted police procedures.’

Red Herring departed, and Jack and Mary ducked under the ‘Police line—do not cross’ tape into the library. They cautiously approached the desk where lay the corpse of the old lady, with her throat so entirely cut that, upon an attempt to raise her, the head fell off.

‘This MO seems somehow familiar,’ mused Spratt, looking around for a sharp object and finding nothing.

‘Definitely locked from the inside,’ added Mary, having made an impossibly rapid examination of the room. Luckily for them both, the dark-humoured pathologist stereotype was the guest of honour at the Mystery Contrivances Club dinner, and was able to give an improbably precise time of death.

‘About 7.02, give or take nine seconds,’ he said, munching on a sandwich.

The first suspect they spoke to was Unshakeable Alibi, who presented them with a photograph of herself taken earlier that evening—with a clock prominent in the background that read precisely 7.02.