The original script for The Predator had Dutch coming in during the third act to help save the day. It was initially set up that way, but when Arnold got the script, he turned his nose up at it. He wanted more than a glorified cameo. So, he turned it down. The ending had to be rewritten. But there's a little more to the story. Speaking with Digital Spy, Shane Black explained exactly how it all went down.
"The studio wanted a fresher movie that featured an evolving cast. They didn't want to hinge the movie on the re-emergence of Schwarzenegger. It would probably be more of a matter of his showing up briefly and just participating at the very end, at the climax of the movie. Understandably, and believe me, I completely get it, he said, 'Look, that's kind of a small part, and I don't really think I want to do that. I'm off to do Terminator with Jim Cameron, basically. Or for Jim Cameron'.
This is the fourth Predator movie, not including the two Alien Vs Predator mashup crossover movies, making six in total. With the franchise three decades old at this point, it is kind of crazy that Arnold Schwarzenegger has never returned as Dutch, especially since his character lived. Dutch gets name dropped in both Predator 2 and Predators
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