This documentary is less about the technical reason for the boiler explosion and more about the human stories. Unlike another reviewer, I loved the background on the Civil War. The description of the prison camps was heart-rending. It helps you understand the mental and physical state of the soldiers aboard the ship. The film did not shy away from the corruption that put a couple thousand soldiers on a rickety old boat. There were so many touching stories about the rescues that followed the sinking. I knocked off a star for the lack of explanation of the boat wallowing and causing a flash steam explosion. Note there was no Confederate conspiracy. The History Detectives did a show that debunked all this nonsense. Some people claimed there was a firewood log filled with explosives. Thing is, the Sultana was fired with coal. Check out this soldier's description of the prison camp at (8:24): "Oh the suffering from cold, hunger, and the petty tyranny of cowards clothed with a little brief authority." I wonder if a soldier today could compose something so moving.