This is the first production of "Witness for the Prosecution" that is based on Agatha Christie's original short (23 pages) story first published in the January 31, 1925 edition of Flynn's Weekly under the title 'Traitor Hands'. She republished it in 1933 under the present title as part of a collection called 'The Hound of Death and other stories'. Christie expanded the story for her 1953 play, changing some of the character names and introducing Sir Wilfrid Robarts as the defense counsel. It is the play, not the short story, that has been the basis for all subsequent television and film versions.
Agnus Dei or Lamb of God a 17th century oil by Spanish Baroque artist Francisco De Zurbaran is seen in Emily's House. It is a signature of Sarah Phelps Christie's and appears in all 5 of her adaptions.
Andrea Riseborough bears a striking resemblance to Elsa Lanchester, who was part of the original 1957 production of the same story.