Mrs Carslake is a non-canonical character who was created for the adaptation of In a Glass Darkly, the second episode of the Thames Television series The Agatha Christie Hour. She is the mother of Neil Carslake and his siblings Alan and Sylvia.
Mrs Carslake was played in the film by Elspet Gray. This character does not appear in the original story although hhr existence is implied since the narrator had gone down to Badgeworthy as a guest of Neil Carslake and said that he "was feeling a little shy at the prospect of meeting his (Neil Carslake's) people for the first time."