If I were Bunty I would be wary who I would get friendly with such as dodgy antique dealer in this episode. They tend to be the rum kind.
Aldous Kemp and his Tanganyikan daughter Grace arrive in Kembleford for the County Fair to sell a valuable item so he can pay for her training as a doctor. They are staying at a hotel and Kemp receives a note telling him to protect himself and then is found dead.
The police arrest his daughter Grace who had argued with her father. Then suspicion falls on John Hammond the gunsmith's son who also knew the victim back in Tanganyika.
Father Brown thinks that a link to the murder goes back to colonial lands and both Kemp and Hammond had skills to develop forgeries that someone took advantage of.
Although I liked the mystery this one felt mundane to me after the last few ones in the run. I just felt it was too easy to figure who the culprit might be but not why they did it.