Long focal telephoto lenses were used for the scenes showing the gendarmes and the media watching the farmhouse at a distance, whereas 40 and 50mm lenses in contrast where used for the tight interior scenes showing the father and his children gathered in defense against the outside world.
The director Robert Enrico was interested in making a film based on the real life incident in 1970s France of a father barricading himself and his children in the country, and had a script written, but did not succeed in shooting the drama until over two decades later.
The story takes place in Tarn et Garonne, the same French region where another film from the same director Robert Enrico - LE VIEUX FUSIL - was shot.
In the real story in which this movie is inspired from, the father killed both his son and daughter and then killed himself, just before the assault. In the film, it is not actually shown, just supposed, suggested. And no line explains it before the ending credits unroll.