12 Monkeys is unabashedly strange. It's a genre-defying, often confusing, thrilling ride that, with today's context, doesn't seem as unrealistic as it did when it was first released in 1996. To many, 12 Monkeys is a cult-hit and nothing short of a masterpiece, much like Batman: Mask of the Phantasm. And yet, when the movie was first shown to test audiences... it was a disaster. When the critics got a hold of it, the narrative changed.

On top of this, making the movie was no easy feat... especially due to how ambitious and complicated the story of time-travel, pandemics, and the mentally-ill was. Here's the truth about the making of the Bruce Willis-led flick...

It Was Based On A Short Film

According to a fascinating article by Inverse, co-screenwtiter David Peoples said that he and his wife (Jan) hadn't seen La Jetée when it was released in the '60s.

"[Charles Roven] sent us a terrible video of it, but in spite of the fact that it was an awful video, it really was such a wonderful movie," David told Inverse. "We said, 'We'll spend a weekend on it and see if there's anything we can come up with that would be interesting.'  It did come to us that people hadn't been doing a lot of stuff with the threat of germs – man-made germs or germs from nature. We had an image of a city with no people and just animals roaming around, totally out of place. Chris [Marker] hadn't said it was OK to make a movie out of his movie. He hated all Hollywood movies except Vertigo."

It was actually acclaimed director Francis Ford Coppola who went to bat for his friends Janet and David Peoples and told Chris Marker that he should allow them to make what ultimately became 12 Monkeys.

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Hiring The Right Director Who Fought For The Movie's Absurd Elements

Then came the search for the right director. Right from the start, Charles and the Peoples thought that Terry Gilliam was the right choice. Terry obviously had a sense of humor as he was part of Monty Python and was behind much of the success of the troupe and their Broadway musical, Spamalot. Terry was also an accomplished filmmaker with an eye for the strange, dark, and deep.

"Terry read it and liked it a lot, but he was totally devoted to a long-time project to make A Tale of Two Cities for Warner Brothers," David explained. "So he had to say no to 12 Monkeys, at which point Chuck [Charles Roven] had us do another rewrite which he thought would make it appealing to other people. In the meantime, something went wrong with A Tale of Two Cities, and suddenly Terry's available again. So we gave him the rewrite we'd done for Chuck and he said, 'How come you ruined the script?'"

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Terry was really attracted to the original script that he read for the very reason why so many other directors weren't...

"I was told by Chuck that it had been read by many different directors and nobody knew what to do with it," director Terry Gilliam said. "That's what excited me about it. The complexity was one thing that was intriguing. Who is the mad person in here? Is it Madeleine [Stowe]'s character or is it Bruce [Willis]'s character?"

What really made the psychological aspect of the movie fly was that both Janet and David Peoples worked in state hospital mental institutions when they were young.

"We both remembered instances of sitting in staff meetings with the doctors all there and the patient not in yet, and one doctor would say something like, 'Oh, by the way, what's the date today?' Then when the patient came in and they started asking him, 'Do you know what the date today is?' it would be a big deal if they knew that stuff. That's what Terry likes, because Terry has this sense of absurdity that is just wonderful," David explained.

But In Order To Make This Movie... They Needed A Movie Star... Enter Bruce Willis

Universal Pictures eventually gave Terry Gilliam a budget of $29.5 million to make his dystopian, pandemic, time-travel, mental institution drama... but they demanded that he cast a movie star in the leading role.

"The pressure was to get a movie star in. That was at a time when I was still a hot director, so people wanted to come near me and touch me," Terry Gilliam said. "So they were coming up with all these names. And I just kept saying no. Tom Cruise, Nic Cage, they were all being thrown at me."

When Terry was presented with Die Hard star Bruce Willis, he rejected him flat out. But eventually, Bruce convinced him to cast him the role.

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"I had never been a great fan of Bruce's before, but I liked talking to him, and I thought, OK, this guy's smart; he's funny. I explained to him my concerns about him as an actor," Terry explained.

After finding a way to get past the things he didn't like about Bruce, he signed him on and the movie was well on its way to make a big impact with audiences around the world.

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