With a swirl of his tail coat, he headed towards the front door, leaving the rest of them studying the contents of their envelopes.

The first card Posy pulled from hers read: You are the murderer. Tell no one!

She rolled her eyes, and shuffled the card to the back to read the instructions behind it.

Sit on the bench in the Murder Spiral, and wait to be approached. When investigators ask where you were when the murder was committed, tell them you were with your fiancé, and kiss him firmly for evidence!

‘Apparently I need to go and linger by the Gate House,’ Rosalind said, her tone dry with annoyance. Obviously she felt that a national treasure of her acting status was above such activities.

‘Well, I’m at the cake stall,’ Caro said, cheerfully. ‘So that’s all right by me. Have fun, everyone!’ She departed with a small wave over her shoulder, her white gloves bright in the sunshine streaming through the window. Rosalind waited a moment, then followed.

‘What’s a Murder Spiral?’ Kit asked, frowning at his own card. ‘Because it doesn’t sound like the ideal place for a romantic rendezvous for me and my fictional fiancée.’

‘I don’t know, but speaking as the aforementioned fictional fiancée, at least we’ll be risking our lives together.’ Posy pulled the map from her bag and studied it, mentally clocking the distance between the Murder Spiral and the folly. ‘Apparently it’s in the gardens, behind the house.’

‘I suppose we better go find it, then.’ He gave her a wink. ‘See if it’s as cosy as it sounds.’

The Murder Spiral was easy enough to find; a large, printed sign with the convention logo and ‘Murder Spiral’ written on it had been attached to a curved wall segregating a circular garden from the rest of the grounds. Underneath that sign sat an older, more official plaque, that Kit stopped to read.

‘Does it tell you why it’s called a murder spiral?’ Posy asked.

Kit tapped a finger against the edge of the sign. ‘Apparently it’s a circular garden planted in a spiral, like they used to do with herb gardens.’

‘I’d sort of guessed the spiral part. What about the murder?’

He pulled a face. ‘This herb spiral is planted with all the poisonous plants Lettice Davenport ever used in any of her books.’

‘Of course it is.’ Still, she checked over Kit’s shoulder to make sure he wasn’t teasing her. He wasn’t.

Planted in 1976 to celebrate the release of her fiftieth book, the Spiral Garden is a commemoration of Lettice’s place as the Princess of Poison in the canon of Golden Age Crime Writers.

They didn’t call it the Murder Spiral, she noticed. Probably Marcus had added that to the maps for an added bit of death and danger.