Melville began filming without the rights to Vercors' novel; when Vercors heard of this, he met with Melville, who told him that if he did not like the film, he would burn the negative. Melville was also not in the screenwriters' or directors' unions and had difficulty in employing people and getting distribution. However, the film was an immense success, both critically and commercially and Vercors loved it.
When the author of the original novel, Vercors, objected to Melville adapting his book without obtaining the rights, the filmmaker made him a deal. The filmmaker would go ahead and make the film without permission, and when it was complete, Vercors would arrange a screening of it for 24 former Resistance members. If even one of the 24 objected to the film, he, Melville, would personally burn the negative in front of Vercors' own eyes. When Vercors arranged the screening, he assumed that only 26 people would be present: himself, Melville and the 24-member "jury." However, much to Vercors' chagrin, Melville "stacked the deck" by instructing his publicist to invite many prominent critics and literary figures, including André Malraux and Jean Cocteau (whose novel Melville would later adapt into the film Les Enfants Terribles (1950)), although Melville feigned innocence in the matter. Of the 24 "jury" members, one dropped out just before the screening, and the editor of the French newspaper Le Figaro was recruited as a replacement. When the film was over, 23 voted in favor of the film and only one against: the Le Figaro editor. However, when Vercors discovered that the man had voted against the film not because of the work itself, but because his vanity was offended at being a last-minute substitute, Vercors discounted his vote, and the film was saved.
Partly because they used natural light whenever possible, and partly because they wished to emphasize, for thematic reasons, contrasts of light and shadow, Melville and his director of photography, Henri Decaë (whose first feature film assignment this was) shot many scenes much darker than was the rule in French cinema at the time. As a result, when the film was sent to be developed, the laboratory alerted Melville to the shadowy scenes, assuming a mistake had been made.
The film's pioneering (in the context of French cinema) use of extensive location shooting and natural light on a very, very low budget inspired the younger filmmakers of the French New Wave to make their early films, which were similarly inexpensive, in the same fashion. This is somewhat ironic, however, because Melville all his life hated location shooting, preferring the controlled environment of the studio.
According to French cinema scholar Denitza Bantcheva, who wrote a book about the filmmaker, Jean-Pierre Melville first read the 1942 novel by Vercors (Jean Bruller), upon which this film is based, not in the original French, but in a hastily-prepared English translation in 1943 in London, to which Melville had temporarily fled due to his activities in the French Resistance. He immediately decided that his first feature film would be an adaptation of this book. In France itself, the book had to be distributed clandestinely, due to the fact that Vercors was himself a member of the Resistance.