It's not a biopic.
Ok, of course this is something you already knew about The Shawshank Redemption but as the movie was gearing up for production, this was actually very unclear. Frank Darabont had to shorten the movie's name from King's original title, Rita Hayworth and the Shawshank Redemption, after agents kept pitching actresses for the lead.
Stephen King licensed the story for a dollar.
Since 1976, the prolific author has offered the Dollar Baby deal. The Master of Horror will let aspiring filmmakers adapt his short stories for a single U.S. dollar. Contrary to how some have interpreted this, King still retains the rights to the stories. It's more of a license for noncommercial use. Nevertheless, Darabont was one of the beneficiaries of the Dollar Baby deal. Eventually King was sent a $5000 check for the movie, but he never cashed it. He framed it and sent it to Darabont.
Rob Reiner wanted to direct.
The filmmaker responsible for This is Spinal Tap, The Sure Thing, When Harry Met Sally, and A Few Good Men was so in love with Frank Darabont's script for The Shawshank Redemption, he offered to buy it for $2.5 million so he could direct it. Reiner, of course, is no stranger to Stephen King stories: he directed Stand by Me, adapted from the King novella The Body, and 1990's Oscar-winning Misery.
Tom Cruise could've starred.
Rob Reiner wanted to put Tom Cruise, who he'd just worked with in A Few Good Men, in the lead role of Andy. He was interested in casting Harrison Ford as Red.
At least a half dozen A-Listers were considered for Andy.
The pivotal lead role was offered to Tom Hanks, who was already committed to Forrest Gump, and Kevin Costner, who was making Waterworld. Other actors reportedly considered include Nicolas Cage, Johnny Depp, and Charlie Sheen.