In April of 2014, the city of Flint, Michigan switched its water supply from nearby Detroit to the Flint River in a cost-cutting measure meant to save the city millions after its economic fall. The consequences were immediate, and disastrous, but through secrecy, denial and bungled management, nothing was done. Two years later, there’s a state of emergency in an American city - its residents mostly poor - cannot drink the water that flows out of their taps, and messages both leaked and released show that the city knew well before any steps were taken.