This is the second movie that Joseph Cotten and Teresa Wright appeared in together. They were previously in Alfred Hitchcock's L'ombra del dubbio (1943) as uncle and niece.
At the time the film was made, Howard Hughes owned TWA, the airline Joseph Cotten and Teresa Wright fly on the first leg of their trip. Hughes also designed the plane, the Lockheed Constellation, but at the time federal regulations forbade airlines from buying planes from their parent companies. So Hughes licensed the design of the Constellation to Lockheed and bought the planes from them.
The Osbornes attempt to board a Chicago and Southern Airlines flight in New Orleans for Brazil. Chicago and Southern Airlines was the name of a real carrier based in Memphis, TN. In 1953, they were integrated into Delta Airlines.
The United States would not have an extradition treaty in force with Brazil until 1964.