MacReady: Christopher Walken, Jeff Bridges, Nick Nolte, Sam Shepard, Tom Atkins, and Jack Thompson, Brian Dennehy, Kris Kristofferson, John Heard, Ed Harris, Tom Berenger, Scott Glenn, Fred Ward, Peter Coyote, and Tim McIntire. Eventually, the role was played by Kurt Russell who knocks it out of the park.
Childs: Geoffrey Holder, Carl Weathers, Bernie Casey, and Ernie Hudson. They went with Keith David, and it was his first film role. Until then, he'd only ever done theater and needed to adjust his technique for the camera.
Palmer: Jay Leno, Gary Shandling, and Richard Fleisher were considered before they went with David Clennon.
Garry: Powers Boothe, Lee Van Cleef, Jerry Orbach, Richard Mulligan, and Kevin Conway before they went with Donald Moffat.
The Thing works on so many levels and truly belongs in the pantheon of great movies. If you haven't seen it, you should. Although, it might be unsettling to watch. I can't imagine the film being better with a different cast, as each person brought something to the role. However, had Nolte been cast as MacReady, perhaps the producers of another film released in 1982 would have gone with the original casting ideas
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