The investigation that exposed a predatory network of human traffickers. With exclusive access to police and the court case, see how they brought down the family crime group behind the UK's biggest human slavery operation.

On a hot summer evening two months ago in the Lebanese capital of Beirut, a catastrophic explosion ripped through the city. It looked like a scene from a disaster movie, but it was very real.

Four Corners pieces together the story of the explosion, tracking down many of the people who filmed the blast as well as those who were dramatically shown on screen.

Using previously unseen footage, the program tracks the final minutes of the emergency responders who had no idea what they were walking into.

In this city with so many connections to Australia, the pain and grief is immense, as is their anger.