This week marks twenty years since rapper Tupac Shakur was murdered. The rapper was shot dead on the streets of Las Vegas in Los Angeles. His family had originally intended for his ashes to be buried in Soweto, which they considered to be the birthplace of his ancestors. Meanwhile, two decades later, still no-one has ever been brought to justice for his murder. And the story of his death is now being taken on by Hollywood directors, years after the case closed. Frances Read reports from Los Angeles.