On a hot August afternoon in 1972, John Wojtowicz rushed into a Brooklyn bank, demanding money in a desperate effort to finance his lover's sex-change operation. So began a chain of events that became the basis for Sidney Lumet's 1972 film, Dog Day Afternoon. What had begun as a quick robbery soon turned into a sensational hostage hold-up drama, a 14-hour war of nerves in which not only the police and passers-by became involved but also the media. Based on a True Story returns to the scene of the crime, with the intention of reconstructing the events of that day through archival footage and interviews with John Wojtowicz and others. But from this relatively uncomplicated premise, the film evolves into a complex investigation of the nature of truth in documentary making. As the filmmaker soon realises, getting the truth out of Wojtowicz is no simple matter. In the intriguing and often hilarious cat-and-mouse game that ensues, Wojtowicz once again claims centre stage, insisting on his authority over the story and the events he caused.