Iranian documentary filmmaker Taghi Amirani, while researching to make a documentary about the coup d'état of 28 August, obtained documents that have been hidden from the public and most historians in the field for decades. Documents that have shed light on many of the dark corners of the event's 67-year history. Coup d'etat is the product of ten years of digging up secret documents and insisting on evidence to understand the astonishing details of the coup. In this respect, the film tells the story of the coup d'état of 28 August, which has never been seen on the cinema screen.