After Colonel Reginald Adams and his actress wife Anne-Marie have forbidden their young daughter Ruby to marry her tutor, the American communist John Van Ert, Anne-Marie is found drowned. Inspector Valentine believed she fell in the lake whilst drunk but Father Brown proves it was murder. Learning that the couple argued, Valentine arrests Reginald just as Anne-Marie's long-lost brother James Trewlove arrives from Nairobi. Anne-Marie's will leaves James nothing, with the chief beneficiary being the church whilst Ruby is bequeathed the Flying Stars,a valuable necklace. During a performance of a play at the Adams' house the necklace is stolen. Father Brown manages to unmask both thief and Anne-Marie's killer.
A nice entry with some fine mystery and fine acting - lady Felicity is up to her tricks again, falling for a long lost brother of the victim - or is he? Is the killer the boyfriend of the victim's daughter? You have to watch to find out.