Father Brown is only too happy to interfere with the work of the police in solving tricky criminal cases, usually with resounding success. That's why the clergyman is transferred to a sleepy island called Abbott's Rock. At first, nothing happens there, but somehow Father Brown seems to be attracted to crime: Soon a gang of thieves is up to no good on the island. So Brown makes the headlines again, and is punitively transferred once more. This time he finds himself in a quiet Irish millionaire community.

Father Brown starts solving crimes, much to the annoyance of his housekeeper, the police and especially his bishop, who is not amused by a priest playing detective.

Small time crook Napoleone falls into an unlikely gang made up of a gangster, called The Baron, and his two cohorts, Agonia and The Captain, where Napoleone takes them to Rome where they shack up with a shady used car dealer caled Il Cajella to help finance their new life of crime by planing to rob a statue from the Vatican. But a big-time American gangster, named Joe Ventura, hears about the heist and wants the priceless statue for himself by having his mistress, Samantha, come onto and betray the woman-hungry Cajella to give the statue away to her.