In July 2013, while Pope Francis is in Brazil, a letter reaches his office from an unlikely address: Rome's Regina Coeli prison. Its author is Monsignor Nunzio Scarano, head of the special accounting section at APSA, the Vatican body that manages the Holy See's wealth, already jailed on charges of bribery, slander, and money laundering. The film follows what put him there: an attempt to smuggle 26 million dollars from Switzerland into Italy by private jet, arranged with a broker, an armed guard, and a Carabinieri officer, on behalf of a Neapolitan ship-owning family. Author Gerald Posner, who wrote a history of Vatican banking, walks through how the Institute for the Works of Religion, the Vatican's own bank, fits into a city-state of 44 hectares and 839 residents with the highest per capita income in the world. The film treats Scarano's case as a way into that larger machinery, tracing how a sovereign enclave inside Rome came to run a bank answerable mainly to itself.