The Blue Cross

International thief Flambeau (John Light) forewarns Father Brown of his intention to steal the priceless relic, The Blue Cross, from St Mary's. To pre-empt the theft, Brown takes the cross in what becomes a battle of wits between the two men. The climax reveals a connection between the two men when Brown fought as a 17-year-old soldier in Flanders during the Great War before taking Holy orders. First appearance of John Light as Hercule Flambeu. Final appearance of Kasia Koleczek as Susie Jasinski.