When Poirot examines the hotel register for signatures of previous guests, he discovers the names of several international celebrities during the 1930s, including Cole Porter, around whose music the film score is derived; Ivor Novello; Maurice Chevalier; Fred Astaire and his sister Adele Astaire; Charles Chaplin; and possibly Marlene Dietrich. An entry listing a home address is listed as Berlin, although the signature is illegible aside from the capital M and D). The register is likely a private joke by the filmmakers since it appears on-screen for only a brief second or two.
The film relocates the provincial North Devon, England setting on Smuggler's Island off the Devonshire Coast from the Agatha Christie source 'Evil Under the Sun' novel to an island in the Adriatic Sea "somewhere west of Suez", a setting played by the exotic Spanish island location of Majorca. The film's screenwriter Anthony Shaffer once said of this: "The location is important. The island should be a star. Just as the Nile steamer [in Death on the Nile (1978)] and the Orient Express [in Murder on the Orient Express (1974)] were stars". Majorca also was at the time the home of the film's director Guy Hamilton.
The game that Odell Gardener is playing when Poirot asks him about his whereabouts during the murder is pétanque, a French game in which players have to throw hollow metal balls as closely as possible to a wooden one.
The characters of Reverend Stephen Lane and Major Barry in the source Agatha Christie's novel 'Evil Under the Sun' were removed for this motion picture adaptation. Other minor characters were also dropped.
After The Mirror Crack'd (1980), this was the second and final Agatha Christie adaptation directed by Guy Hamilton. Hamilton directed the films consecutively and, prior to the first film, had not been "totally enamored" of the Christie books.
This motion picture was selected to be the 1982 Royal Film Performance. The film screened on Monday 22nd March 1982 at London's Odeon Theatre, Leicester Square in the gracious presence of Her Majesty Queen Elizabeth II with proceeds from the charity UK premiere going to the Cinema and Television Benevolent Fund. However, this screening was not the world premiere of the film, it had debuted in Australia a month earlier in February 1982, the picture launching down under there because EMI's Can't Stop the Music (1980) had had its best box-office returns there.