When a young girl slips away from a Jane Austen weekend dressed in period attire, and is found stabbed in the woods, Barnaby needs to look back in time to find the killer.Journalist Samantha Berry is killed whilst attending a Regency-themed weekend run by Kitty and James Oswood, apparently on her way to receive information. The murder weapon is a poisoned quill, stolen from Gemma Christie's Jane Austen tea shop though Barnaby is also interested in a drone delivery service used by James' stepmother, pharmacist Mary Oswood, whose premises are broken into and its computer destroyed. James clearly has a guilty secret Samantha was keen to expose but when a drone, borrowed by Ray, Kitty's brother-in-law, is involved in another murder Barnaby must work out whether Oswood's past or opposition to the drones caused death by persuasion.