A new documentary suggests we don't know jack (get it?) about what caused the Titanic to sink. Many people believe that the 1912 sinking of the Titanic was due to a collision with an iceberg, which punctured holes in the ship and caused it to take on water. That belief was seemingly confirmed by the 1997 film Titanic (maybe you've heard of it?), which depicts the crash as the cause. However, upcoming documentary Titanic: The New Evidence posits that the iceberg didn't take down the massive ship alone. The doc, which will premiere on the Smithsonian Channel on Saturday, January 21, examines photo evidence from the ship's chief electrical engineer, John Kempster. What these photos reveal could change your perspective on the ship's story. It looks like the so-called "unsinkable" Titanic was not nearly as strong as she was purported to be prior to her maiden voyage. As reported by Entertainment Weekly, the most significant evidence the film presents comes from two photos, which show a 30-foot long black streak on the ship's hull that was present before the ship ever went to sea. Experts believe the streak is evidence of a fire in a coal bunker below deck, which may have caused damage in the very same region where the ship came into contact with an iceberg. While the Titanic did hit the iceberg, it was the tragic combination of a weakened hull and the collision that took down the ship — and, according to the documentary, it could have been avoided. Journalist Senan Molony, who speaks in Titanic: New Evidence, believes that the sinking was a result of "criminal negligence." “The fire was known about, but it was played down. [The Titanic] should never have been put to sea.” 1,503 people died on the Titanic, and the news that the disaster could have been avoided makes that all the more devastating.