Before she took her vows and entered St. Vincent's Convent, Sister Boniface (Lorna Watson) was a Bletchley Circle codebreaker with a Ph.D. in forensic science... and as such, her input was gladly welcomed by the constabulary of Great Slaughter. Engaging, '60s-set mystery series spun out of "Father Brown" also stars Max Brown, Jerry Iwu, Miranda Raison, Ami Metcalf, Belinda Lang, Carolyn Pickles, David Sterne, Sarah Crowden.8 episodes on 3 discs. 6 hrs. Widescreen; Soundtrack: English; Subtitles: English.