Some of the Latin American exterior footage that is seen behind the opening credits, and which is inter-cut with the studio-shot scenes and projected behind the cast in some sequences, is rumored but unconfirmed to have come from Orson Welles' never-completed and Brazilian-located RKO documentary "It's All True"; that project was itself the subject of a documentary, It's All True: Based on an Unfinished Film by Orson Welles (1993).
Romero's first car, at the airport, is a 1929 Pierce-Arrow 125. An example of this car in excellent condition in 2021 could be worth upwards of $100,000 or more. His second cars are a 1941 Oldsmobile 78 (blackwall tires at first) four-door sedan and that turns into a 1941 Oldsmobile 98 four door sedan (with whitewall tires). His third car is a 1940 Chevrolet Master Deluxe four-door sedan.
The "woody" station wagon in which Martha Vickers sneaks off from the station was also seen in The Falcon and the Co-eds (1943), where it appeared as the "school bus" for the Blue Cliff Girls' Academy. With the cessation of automobile production during World War II, even movie studios had to hold onto their pre-war production cars longer than usual.
The American Airlines plane depicting The Falcon and Barbara flying to Mexico is a 1937 Douglas DC-3A, registration NC17338, named "Flagship Philadelphia". It was with various subsequent airlines and under other registration numbers, and was still flying when it was destroyed on the ground in Puerto Rico by Hurricane Hugo on September 18, 1989.
The ninth of sixteen movies for the suave detective nicknamed "The Falcon" and the sixth of ten starring Tom Conway.