The Kembleford Boggart

The domineering father (Simon Williams) of a successful young writer, 22-year-old Hannah, is murdered in a locked room and the only suspect is an itinerant traveller who comes to Kembleford every year in a caravan with his mother. Father Brown's suspicions are aroused when the murder has the hallmarks of a boggart, an unwelcome infant from another world created by Hannah in her book.