[citation needed] In South America, the daunting mountains and dangerous weather have hampered the operations of Trans-Andean European Air Mail, a 1930s-era airline.

Charged with delivering a serum to stem an outbreak of infantile paralysis in Rio de Janeiro, Auguste Pellerin (Robert Montgomery) conquers his fears, but is reprimanded by the airline's stern director, A. Rivière (John Barrymore) for coming in late.

The pair are caught in a torrential rain storm and when Madame Fabian (Helen Hayes) comes to the headquarters, she realizes that her husband is overdue.

The pilot despairs that his flight only meant that someone in Paris can get a postcard on Tuesday instead of Thursday, but its real value is proven when the serum is also delivered and a child is saved.

Saint Exupéry's Vol de nuit, based on real-life events in South America, had won the 1931 Prix Femina, one of the main French literary prizes (awarded by a female jury).

[6] Selznick realized that Oliver H. P. Garrett's original treatment was too heavily based on "the ground" and brought in John Monk Saunders, who had worked with him on The Dawn Patrol (1930), to add more flying scenes.

Night Flight utilized both studio and location shooting with the mountainous region around Denver, Colorado, filling in for the South American Andes.

[14] Smarting from some critics' reviews of his novel, and professing that he hated the film adaptation, Saint Exupéry refused to renew his author's rights, which he had granted to MGM only for a 10-year period.