At one point Lola Brewster refers to having "Alexander" brought in to do her hair. Elizabeth Taylor, playing Lola's rival Marina Rudd, had her hair done for the film by Alexandre (Alexandre de Paris).
Natalie Wood was the first choice for Marina Rudd but turned the role down after disagreements over cast billing and the portrayal of the character itself.
Although Angela Lansbury's character is presented as elderly and the leading men as only middle-aged she, Tony Curtis and Rock Hudson were all born the same year - 1925.
The publicity department committed a legendary faux pas by issuing a press release regarding one of the stars, claiming that for the first time in that performer's long career they played a murderer, thus giving the solution to the mystery away.
Pierce Brosnan's first brush with James Bond has him working with Guy Hamilton, director of Goldfinger. It would take another 15 years before Brosnan landed the role of 007 .
Miss Marple tells her nephew that she knows drugs and poisons from her "days at Bridgehampton hospital during the war". Agatha Christie learned about poisons working at the Torquay hospital dispensary during the first world war.
The title comes from Alfred Lord Tennyson's celebrated Victorian poem "The Lady of Shalott": "Out flew the web and floated wide; / The mirror crack'd from side to side; / 'The curse is come upon me,' cried / The Lady of Shalott."
The film is set in 1953 - hence the Saturday village fĂȘte being thrown in aid of the Coronation fund (referring to the Regal Coronation of Queen Elizabeth II on 2nd June that year).
The portrait shown on the Gossington Hall staircase is genuinely a copy/interpretation of Giovanni Bellini's "Madonna and Child" artwork, as specified in Agatha Christie's source novel.
Half of the plot - the backstory that's revealed at the end - seems to be inspired by the real-life drama of Gene Tierney and her husband Oleg Cassini. After a measles-infected fan broke quarantine and rushed up to the pregnant Tierney to kiss her, the actress gave birth to a daughter, Daria, who is still in a care facility for the profoundly brain-damaged.