Titanic (film) trivia: The moment where Jack and Rose are racing down the hallway outrunning the rising water was one of the world’s first digital face replacements. Due to the extremely high levels of danger and difficulty required for this moment, the scene was originally shot with Kate and Leonardo’s stunt doubles running down the hallway and Kate and Leo had to subsequently make the same run. Their faces were later digitally placed onto their stunt doubles during post-production.

Fred Fleet was the first Titanic crew member to spot the iceberg, and he testified to a senate inquiry that, if he’d had access to binoculars, he might have seen it soon enough to avoid it. The ship would have never sunk, and that one guy would have never fallen hilariously onto the propeller on the way down.

But here’s the thing: the binoculars were on the ship. But they were locked up, and the key to the locker didn’t make the trip. That’s because right before the Titanic sailed, the company that ran the cruise made a split-second decision to replace the ship’s second officer, David Blair, with another guy, Charles Lightoller, who had more experience working on giant ships and was thus less likely to, say, get them all run aground on an iceberg. So Blair missed out on the cruise of a lifetime, but as he waved goodbye to the departing Titanic, he neglected to realize that the locker keys were still in his pocket.

6 Tiny Mistakes That Changed The Course of History