Coffin of Light (2009)
A look back on the Spanish horror film industry of the '70s which follows Sergio del Monte, a cinematographer turned director who was murdered mysteriously three days into the making of his film debut, apparently due to the issues he dealt with in his picture. According to the facts, he was using some revolutionary lighting technics to show an alternative reality that the human eye can't see. After his death, the producers involved in the backing of such project also died from a brain tumor after watching the remaining footage. It was suspected that these deaths were in fact caused by extreme right wing groups who after Franco's death were afraid the regime to fall apart so they went onto a killing spree in order to preserve it.