Despite its geographical closeness to the United States, Mexico is a country far removed from its rich neighbour. Decades of struggles between different cartels, police, the military, local militias and the American war on drugs has left much of the country in a state of lawless poverty. In many places, society, as we know it, has broken down completely and it has become impossible to tell the difference between the good guys and the bad guys.

Dark Suns, the new documentary from Julien Elie, is an epic investigation into the seemingly unchecked murders, mutilations and disappearances taking place across the country. Using testimonies those families who have lost loved ones, he paints a picture of a society where the authorities are no better than the drug lords. Instead of being polar opposites they are often allies or competitors.

Whilst Dark Suns is more of a marathon than a sprint, Elie’s decision to allow the victims to tell their own stories in their own time really pays off. He chronicles the atrocities, the cover-up and the myriad disappearances through the words of the survivors. By collecting these accounts together and giving them the space to breathe, Dark Suns builds up a disturbing profile of a country which is infested by corruption and greed.

Dark Suns screens at Sheffield Doc/Fest on 7 and 9 May.