James Cameron isn’t called “Iron Jim” because he’s an avid weightlifting aficionado. He’s a perfectionist to his core with a very aggressive approach to filmmaking, especially when someone tells him, “You can’t do that.” Cameron tends to be right in the mess with everyone else, pushing for the exact shot, the exact timing, and the exact physics (unless the story needs him to ignore physics for emotional damage)—all to get that one perfect shot.

Here are some of the wildest behind-the-scenes stories from James Cameron’s productions.

The Terminator (1984): Casting Nearly Went in a Very Different Direction

Early casting ideas for The Terminator included Arnold Schwarzenegger as the human hero Kyle Reese and, get this, O.J. freaking Simpson as the killer cyborg, which, in hindsight—wow. The twist is that when Schwarzenegger met with Cameron, he couldn’t stop thinking about the villain. He reportedly broke down how the Terminator should move and behave: no joy, no flair, no monologuing, just pure machine. Cameron realized Arnold was basically explaining the character better than it was currently written. The rest is sci-fi history.

Aliens (1986): How Cameron Got Sigourney Weaver Back

The classic sci-fi horror Aliens feels like a waste of time without Sigourney Weaver’s Ripley, but did you know she had other plans at the time? But Cameron had an eye only for her and refused to accept a half-hearted “maybe.” And so, our boy Jimmy called Arnold’s agent, Lou Pitt, and claimed he’d decided he could simply rewrite the sequel without Ripley, straight up removing her character. This little gambit paid off, as he knew the message would reach Weaver (Hollywood is just a big village). As a result, the deal was back on the table, and even though Cameron didn’t actually intend to cut Ripley, he went all-in, and they didn’t call his bluff.

The Abyss (1989): The Shoot Was Basically “What If Filmmaking, But Underwater, Forever”

If you’ve heard stories about the brutality of shooting The Abyss, they’re not unfounded. Large parts of production took place in a giant tank, with cast and crew spending long days submerged, sometimes at significant depth. Even basic operations got ten times harder because humans weren’t meant to be in the water for hours. Ed Harris nearly drowned during production in a genuinely terrifying incident that he later described as the crew being Cameron’s guinea pigs. Even Jimmy himself almost ran out of oxygen at the bottom of the tank, tried to surface, and swallowed a bunch of water.