This movie was shot partially at the American Colony Hotel in Jerusalem, which was founded by Sir Peter Ustinov's grandfather in 1902.
David Soul wanted to do the film because he had just come out of rehab for alcoholism at the time and wanted to get out of Hollywood for a while. It was while shooting his scenes for this film that he was approached by a theatrical agents who wanted to know if he would be interested in a role in a play for London's West End. Intrigued at the prospect of doing theatre again and being taken seriously as an actor he ended up relocating to the UK in the 1990s and eventually became a British citizen.
Lauren Bacall felt she had been hoodwinked into doing this film. She had previously appeared in another movie based on Hercule Poirot, Murder on the Orient Express (1974), which was primarily shot in a British film studio with a few exterior shots filmed in Turkey and France. She had enjoyed that experience enormously and the film received good reviews. Bacall and several others in the cast had assumed this would follow a similar formula, especially as Cannon Films had appointed an English director to film it. However the Israeli producers wanted to shoot the majority of the film in Israel as a cost cutting measure. Apart from a few days in Italy and about a week in England the film was shot in Israel during the hot summer. Bacall was not terribly happy with the end result or the experience. Apparently director Michael Winner, who had worked for Cannon films before knew that this was the plan but elected not to say anything too early about the filming schedule for fear of putting off his star names.
At the age of 83, Sir John Gielgud was not interested in travelling to Israel to shoot a film in the stifling heat and turned the part down saying he'd much rather stay in England and do some theatre or a television role. Sir Peter Ustinov (who had previously worked with Gielgud on stage) and Michael Winner took Gielgud out for dinner in a posh London restaurant in an effort to convince him to do it with Ustinov telling Gielgud it was "Easy money for a couple of weeks work" and Winner saying that the role would not be too demanding plus it was in a mainstream film with a guaranteed audience around the world. Despite his reservations about the heat of the shoot or the lack of artistic integrity to the project he finally agreed to do it as a favor to both men.
As with the source novel, this movie evoked Agatha Christie's relationship with archaeological husband Max Mallowan as the desert regions, in which the movie and novel are set, are evocative of archaeological digs. Filming location Qumran in the Dead Sea is where the Dead Sea Scrolls were discovered.