"He proved to be so much better than I ever imagined," Gilliam says.

There may be no film in existence that endured a more torturous production than “The Man Who Killed Don Quixote,” which Terry Gilliam attempted (and failed) to make several times over the course of two decades before finally bringing his passion project to Cannes this year. Its behind-the-scenes story isn’t over — Gilliam recently came out on the losing end of a legal battle with his former producer — but the long-delayed movie has, at the very least, seen the light of day.

To hear Gilliam tell it, that’s largely thanks to its star: Adam Driver.

“This film was made because of Adam Driver,” Gilliam declares in an interview with RogerEbert.com. “I had never seen him do anything, aside from ‘Star Wars,’ where he’s doing this [opens mouth in screaming pose] a lot, and I was like, ‘Okay, fine. I don’t care.’”

“But my daughter, who is one of the producers, said, ‘You gotta meet him,’ and I did initially because he was ‘hot’ [at the time]. You meet the people who are ‘hot’, because that’s how you’ll get the money you need,” Gilliam continues.

“The minute I met him, I thought that there was a quality about this guy that was unlike any other actor I had met. There was a stillness and a genuineness, there was nothing actor-y about him, and he proved to be so much better than I ever imagined.”

Gilliam also refers to his leading man as “such a strange actor, because if you just stand him there, he’s kind of goofy looking — he’s tall and gangly, with a big nose and ears that stick out. He doesn’t look like a movie star, but by the end of this film, he looks like one of the most romantic leading men I’ve seen in a while. He just transforms himself, and it’s not coming from anything external, it’s all coming from inside. It’s fantastic to watch.”

Driver is far from the first actor to take on the role: Johnny Depp, Ewan McGregor, and Jack O’Connell have all been attached at one point or another. “The Man Who Killed Don Quixote” was even the subject of a documentary, “Lost in La Mancha,” that charted Gilliam’s failed attempts to complete the film.

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