On April 20, 2010, the Deepwater Horizon oil rig exploded, marking the beginning of the largest marine oil spill in history. But the explosion was only the start of a cataclysmic tragedy that would ravage the environment for years to come. This short documentary by Disaster Diaries breaks down exactly how it happened and the lasting impact it left on international waters. It’s a haunting but necessary look at one of the greatest man-made disasters of our time. Disasters like this are rarely caus