Whilst this adaptation situates St Mary Mead in Oxfordshire, clues given in the books would place the village in Hampshire.
Eileen Atkins and Annette Crosbie were considered for the part of Dolly Bantry.
A calendar on Miss Marple's table shows 1st August 1951 as a Tuesday. In fact, that date fell on a Wednesday.
In this episode, Miss Marple can be seen reading a book called The Simple Art of Murder. Within the book, the author criticises writers including Agatha Christie for creating over-elaborate murder plots in their works of fiction.
Jenny Agutter, who plays Agnes Crackenthorpe, is named among the alphabetical list of guest stars in the opening credits, but her name isomitted from the closing credits.
In the episode the estate and hall that runs along the side of the railway line is called Rutherford Hall.... This is after Dame Margaret Rutherford whom played Miss Marple in four MGM films in the 60's.
Rob Brydon is cast as a character not in Agatha Christie's novel, a certain "Inspector Awdry" of the Railway Police. He is named after the Rev. W. Awdry, whose stories about "Thomas The Tank Engine" have been popular with British children for over 50 years.
During one of the flashbacks, Edith is playing a song called The Sabre Dance on the xylophone. The flashback was supposed to be in 1934, but the song wasn't composed until the 1940's.
Isla Fisher was rumoured to play Gwenda.
This book is noticable for the late appearance of Miss Marple, who doesn't apear until the last quarter of the book.
Goof - Anachronsim: Marple: (To the taxi driver) The train station, not the police station, please.
There's no way Miss Marple would have used this expression in the late 1940s or 50s; the expression has only been in common use for the last three or four years. The term is "railway station".
In an early scene, a character asks for Room 412. This references a famous joke from one of Stan Freberg's routines "St George and the Dragonet" which was a #1 hit record in 1953 and was a popular in-joke at one time in acting circles. The joke's punchline - the Dragnet-style cop says "I've got you on a 412 as well." What's that, shouts the criminal. "Over-acting" replies the deadpan cop.
In the opening, the hotel manager is on the telephone where he can be heard saying "Miss Otis regrets she's unable to lunch today". This is a line from the 1934 Cole Porter song Miss Otis Regrets.
Bertram's Hotel is named after Brown's hotel.
Mr. Treves in the novel does not have a first name. In the program Towards Zero he's given the first name Frederick.
Based on Ms Christie's 1939 novel, Murder is Easy. Murder is Easy is not a Marple novel.