Combustible: The dangerous legacy of failed regulation in the building industry. Across Australia, governments, councils and the building industry are grappling with a problem so large, it almost defies belief. Residential buildings, hospitals, shopping centres and commercial buildings, have been built with flammable aluminium cladding, posing a potentially serious fire risk. It took the catastrophic Grenfell Tower fire in London, which claimed at least 80 lives, to set off alarm bells here, but as Four Corners will reveal, the danger posed by this cladding should not have come as a surprise. Four Corners investigates why huge amounts of this aluminium cladding has been installed on so many of our buildings, and whether a desire to cut costs won out over caution. Insiders say there has been a colossal failure of regulation and oversight. With access to the tests now under way on suspect aluminium cladding, we reveal the enormity of the problem facing authorities and ask who will pay to remove and replace it.

Four Corners is Australia's premier television current affairs program. It has been part of the Australian story since August 1961, exposing scandals, triggering inquiries, firing debate, confronting taboos and interpreting fads, trends and sub-cultures. Its consistently high standards of journalism and film-making have earned international recognition and an array of Walkleys, Logies and other national awards.