<Tr> <Td_colspan="6"> Professor Hilary Ambrose, suffering from memory loss and delusions, seeks the help of Father Brown to solve a riddle over 300 years old relating to an Alchemist who hid a formula believed to turn lead into gold . When one of his students is murdered and the evidence points to Ambrose, Inspector Mallory arrests him . To prove his innocence Father Brown has to solve the riddle, find the hidden formula, and discover the real killer . Discovering the terrible secret of the formula, and the killer, poses a dilemma for Father Brown but explains why an entire village, Thorndyke, disappeared from the map over 300 years ago . </Td> </Tr> <Tr> <Th> 56 </Th> <Td> 11 </Td> <Td> "The Sins of Others" </Td> <Td> Diana Patrick </Td> <Td> Tahsin Guner </Td> <Td> 13 January 2017 (2017 - 01 - 13) </Td> </Tr> <Tr> <Td_colspan="6"> Sid Carter is released from prison after a year following his conviction of assault on Judith Miles, then a prostitute, now working in a solicitors office . Bent on revenge, Sid confronts his defence lawyer Giles Foster, now a judge, with Father Brown at the home of a Edward Reese who appointed Foster . When Foster is found dead from stabbing by a glass to the throat, Sid is accused by Reese's son of the murder . Father Brown becomes a target of a paid assassin and his only clue a pail of ashes . </Td> </Tr> <Tr> <Th> 57 </Th> <Td> 12 </Td> <Td> "The Theatre of the Invisible" </Td> <Td> Bob Thomson </Td> <Td> David Semple </Td> <Td> 16 January 2017 (2017 - 01 - 16) </Td> </Tr>

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