One suspicious death. Two amateur sleuths. And an utterly impossible crime… The Cotswolds, 1924. At the Old Forge in the quiet village of Maybury-in-the-Marsh a cry of anguish rings out: lady of the house Amy Phelps has been discovered dead. But with all the windows and doors to her room locked from inside, how – and by whom – was she killed? Arbuthnot ‘Arbie’ Swift finds himself in the unlikely position of detective. The celebrated author of The Gentleman’s Guide to Ghost-Hunting is staying at the Old Forge to investigate a suspected spectre, but now the more pressing matter of Amy’s murder falls to him too. With old friend Val, he soon uncovers a sorry tale of altered wills, secret love affairs and tragic losses – and plenty of motives for murder. When events take another sinister turn, Arbie must find the killer, fast. And to do so will mean cracking a most perfectly plotted crime…