Written by Guillermo Arriaga, author of Amores perros , 21 Grams and Babel , Upon Open Sky is a searing coming-of-age road trip that unfolds against the arid landscapes of 1990s Mexico. Two years after 12-year-old Salvador survives a crash that kills his father, his older brother Fernando plans a reckless journey north to confront the truck driver responsible. Their stepsister Paula, unaware of their intentions, joins the trip, turning the fraught mission into a complex exploration of grief, justice and the complexities of human morality.