Monday 7 September 2008 saw the start of a major upheaval in the global markets that lead to the greatest financial crisis for 80 years – on this day Fannie Mae and Freddie Mac had to be rescued by the US government. The next day, shares in Lehman’s dropped 45% and crisis talks started. Within 10 days, the map of Wall Street had been redrawn and the shock effect was about to be felt around the globe.

One year on, BBC World News’ Aftershock season is examining the impact of the global recession across its news and business programmes, news reports and live coverage.

In Lehman’s: How a Busted Bank Changed the World, the BBC’s Business Editor Robert Peston examines what happened and what we’ve learned since the day the money stopped. In this new documentary, he meets many of the people who witnessed the demise of Lehman’s, from bank bosses to Wall Street lawyers and government regulators and asks them a year on, if anything has changed.

Sifting through the illusions and misconceptions that took the world to the brink of financial Armageddon, Robert looks at how the global economy will change and what defences we can build to ward off future financial debacles.