As written by Dongala, Johnny Mad Dog features two parallel stories but the story of Johnny and the Death Dealers, some of whom are as young as twelve, drives the story. The kids, who are duped into becoming second line guerrillas, roam from town to town in order to loot, rape and murder their neighbors and friends. The children's notions of war, and even life, are gained from films such as Mission Cobra, Rambo and Raid on Entebbe. They are so lacking in independent thought that when told that their fellow countrymen are Chechens, Israelis or Palestinians, they believe it. The children are aware enough to realize that no matter who the politicians are or what they say, they can do whatever they want. Although the country in which the events transpire unidentified in the novel, Sauvaire shot his film in Liberia. 15 former child soldiers from Liberia, most of whom fought for Charles Taylor's Liberians United for Reconciliation and Democracy (LURD), were cast in the film. Sauvaire used this opportunity to found the Johnny Mad Dog Foundation, which provides support for cast members who were left without family or homes because of the country's civil war.

Johnny Mad Dog was an official selection in the Un Certain Regard program at the 2008 Cannes Film Festival, and subsequently won the Festival's Prize of Hope. The film has been strongly reviewed, and noted for its graphic depictions of these real-life events. In July 2008, Sauvaire screened the film at the United Nations headquarters in New York in order to highlight the real-life plight of children depicted in the film. August 2008 screenings in Los Angeles are planned and the film is scheduled to play at both the Deauville Festival and the Hamburg Film Festival in September 2008. Finally, the film opens theatrically in France on November 26, 2008.