6.40/10 1968-12-22 50 minutes.HDWhilst in Cornwall Holmes is approached by the local vicar to determine how Brenda Tregennis died whilst sitting in a room, playing cards with her two brothers, who were struck down with dementia as a result. The trail leads to an African adventurer and a deadly root known as the Devil's Foot.Year: 1968Studio: BBC OneCountry: United Kingdom