Miss Marple: By the Pricking of My Thumbs (TV)

Tommy and Tuppence Beresford visit their aunt Ada in a nursing home. Aida cryptically mentions to Tuppence about a murdered child. The next day Ada is found dead in her bed. Causes appear to be natural but Tuppence's suspicions are aroused when a note from Ada mentions that fellow-nursing home dweller Mrs Lancaster is not safe. Coincidentally, Mrs Lancaster has just checked out, accompanied by Mr and Mrs Johnson. While pondering all this at the nursing home, Tuppence runs into someone who is intrigued by her musings - Miss Marple. Together, and aided by a painting, they set off to find the Johnsons and Mrs Lancaster, as they are sure they are key to a mystery and potentially a murder, or two.