By the time the Ville de Nancy nears the port of Marseille, France has surrendered to Nazi Germany, and a collaborationist Vichy government has been set up.

Renault's bomber is delayed, as Matrac is allowed to drop a letter over his family's house in occupied France — thus maintaining ties with his wife Paula and a son he has never met — before returning from each mission.

Other actors connected to both productions included Michèle Morgan, who had been the original choice for the female lead for Casablanca; Victor Francen, Philip Dorn, Corinna Mura, and George Tobias.

Before Bogart began work on the film, pre-production had been underway for six months, but as a result of resisting Jack Warner's decision to cast him in Conflict (released 1945, but shot in 1943), his starring role as Matrac was in jeopardy, with Jean Gabin being touted as a replacement.

The production took liberties with the actual bombing campaigns carried out by the Free French units, that primarily employed medium bombers such as the Martin B-26 Marauder.

[5] A scene showing Bogart's character machine gunning the defenseless aircrew of the downed German bomber was cut by censors in foreign releases of the film.

[6] Bosley Crowther of The New York Times favorably reviewed Passage to Marseille, noting the film's "tough and tempestuous melodrama is something of a sequel, as it were, to the comment on Devil's Island which Warner was making five years ago.