Mexican director Amat Escalante defended his ultraviolent film in competition Thursday at Cannes, calling it an accurate depiction of his country's blood-drenched drug wars. Heli, one of 20 pictures vying for the festival's Palme d'Or top prize, offers an unflinching look at an unspeakably vicious circle of underworld crime and vengeance. But its protracted torture scenes, including one in which a character sets the genitals of a suspected cocaine thief ablaze, left several queasy critics running for the aisles. Escalante dismissed critical questions about tormenting viewers while telling the story of a family caught up in gangland battles in an unnamed desert region of contemporary Mexico. "What's the point of not showing the violence just so the audience can go through the story and not suffer so much when actually that's not how violence is in real life?" he asked reporters. "I think I'm curious about sex and death and violence, and so that's all in the film," added Escalante, whose last picture "Los Bastardos", set among the Mexican community in Los Angeles, played in Cannes' Un Certain Regard section in 2008. The latest film features amateur actors, telling the story of a police cadet who falls for the 12-year-old sister of a factory worker named Heli (Armando Espitia). The young officer, training in anti-narcotics operations, steals two packets of cocaine and hides them in the water tank of his girlfriend's family home with the aim of using them to finance their elopement. The stash, however, is quickly discovered, setting off a nasty chain of events that leaves no one unscathed. Film industry bible Variety called "Heli" "an accomplished but singularly unpleasant immersion" in the drug wars and noted that it was the most "explicit, realistically violent film" in the Cannes competition in several years. However Robbie Collin, a reviewer for London's Daily Telegraph, said: "Even a bleak existence can make an uplifting story." "Heli may be the most optimistic film you will ever see in which one young man sets another's genitals on fire," he wrote. The Cannes Film Festival runs until May 26.