Agatha Christie: Murder on the Orient Express stay as faithful to Christie's work and time era as possible. A major difference between "And Then There Were None" and "Murder on the Orient Express" that Sheldon pointed out was that in the former, the premise of the novel was that no one solved the murder. This forced Sheldon to desperately try to find a way to integrate clues into the story so that the player could actually discover the murderer, although the game remained quite uninteractive. In "Murder on the Orient Express", the actual novel follows an investigation, so Sheldon could more easily integrate clues to lead to
Cadillac Calais De Ville, but not the lower-priced Series 62, became standard throughout the Cadillac range – even the Calais. The V8 also remained the standard engine. Pricing of the Cadillac Calais started at nearly US$5,000, almost US$1,000 (or about 25%) more than the Electra 225 and Oldsmobile 98, and about US$500 more than the top-line Buick Riviera. In 1966 changes included a somewhat coarser mesh for the radiator grille insert, which was now divided by a thick, bright metal horizontal center bar housing rectangular parking lamps at the outer ends. Separate rectangular side marker lamps replaced the integral grille extension designs.