This film is based on the true character of Robert (Bob) Denard in the 1960s when he fights in the Democratic Republic of Congo. As a mercenary, he defends President Mobutu, who won his position after a putsch. Despite pressures from the French government who supports Mobutus opponent Moïse Tshombé, Denard stays loyal to Mobutu until the very end, when he understand that Mobutu wants him dead. Denards only solution becomes to get rid of Mobutu, but the French government ends up changing side to support Mobutu. Luckily for him, Denard manages to be rescued after a head injury during combat against Mobutus troops.