Yorkshire, 1926. Gentleman ghost-hunter Arbuthnot 'Arbie' Swift and his old friend Val arrive at Cleeves Lea Manor, looking forward to the promise of a lavish weekend party.

The lady of the house, an avid reader of Arbie’s books, is eager to show him off to her distinguished guests. Amidst the festivities, Arbie is also tasked with investigating rumours of a ‘ghost train spitting fire’ for the third instalment of the increasingly popular (to Arbie’s great surprise) Gentleman’s Guide to Ghost-hunting.

But when the guests start dying, Arbie instead finds himself thrust into the middle of a murder investigation. With time running out, will he and Val be able to uncover the truth?