Amateur investigator Geneva Pomolo and her partner, Iris Reeves, receive invitations to visit a new theme park on the outskirts of Wrangler’s Hill days before Christmas. Perdition Parva is built like a traditional English village straight out of an Agatha Christie novel, at the center of which stands the palatial and imposing Murder Manor complete with all the Christmas trappings. Maids and servants wander the place in vintage garb, along with actors playing stock character types from Golden Age whodunits - the headstrong colonel, the doddering vicar, the slightly barmy fortune-teller, and so on.

But when a real murder occurs on the grounds, illusion quickly gives way to reality. The victim: Stella Paisley, a high society lady notorious in Wrangler’s Hill for flashing her jeweled tiara and collecting boyfriends like diamonds. Struck down by a car in front of the manor house, she leaves behind a number of suspects - all had reason to want her dead: Mila Haskin, a medium and grifter who’s failed at everything she’s ever done; Lucas Rowley, her latest fiancé, who was making big plans with her money even before her death; Maybelina Rochefort, who lost a boyfriend to Stella; Zoey Keats, who lost so much more.

As the investigation deepens and a second murder is attempted, Geneva plunges headlong into a game of wits with a murderer who is both cunning and implacable - and shows no hesitation in wanting to make Geneva and Iris the next victims - and all before Christmas.