Robert Duvall reflects on The Godfather mooning contest, working with Marlon Brando

The story goes that Robert Duvall made James Caan an offer he couldn't refuse.

Driving home from a pre-production cast and crew dinner on The Godfather, Duvall dared Caan to stick his butt out the car window and moon Marlon Brando, sitting in the car across the way. Caan did it and inadvertently kicked off a mooning contest on the set of the classic gangster epic, now celebrating its 50th anniversary. Brando, a consummate prankster, won the contest in the end.

When we ask Duvall if this bit of movie lore is true, he laughs, "Yeah, we did all that stuff," before demuring, "I can't tell you all the stories because my wife will hit me over the head with a frying pan if I do."

But Duvall notes that the jovial atmosphere on set, perpetuated largely by Caan and Brando, was an essential part of making the film into an enduring classic. "[Director Francis Ford] Coppola would say, 'Come on, guys. We got to be serious.' But he knew that by all this fooling around and having fun, it relaxed everybody. Being irreverent in a positive way made the set more loose."

So much so that Duvall says making The Godfather was more fun than making the equally revered sequel, The Godfather: Part II due to Caan's absence. "Jimmy's a lot of fun and he'd tell a joke and it would take Brando three seconds to catch on," Duvall says. "He loved Jimmy. Jimmy was funny the whole time, but he was not in Godfather II. So, The Godfather was a bit more fun."

As Corleone family consigliere Tom Hagen, Duvall shared many scenes with Brando, an acting legend among a passel of young newcomers. "Brando, he takes what you give and he was like the godfather to us," Duvall recalls. "Dustin Hoffman, Gene Hackman, and I would meet once a week at a drugstore in New York City years ago. If we mentioned Brando's name once, we would mention it 25 times because he was an inspiration to a lot of young actors."

Duvall also got to witness one of Brando's acting quirks: his use of cue cards placed around the set to help him remember his lines. The technique is visible in the exclusive video above, a clip from one of Brando's home videos taken while rehearsing and shooting Vito Corleone's death scene. The clip is part of a passel of special features on the new 4k Ultra HD release of The Godfather trilogy.

Many have pointed to Brando's use of cue cards as a symptom of laziness or forgetfulness as he aged. But Duvall tells EW it was just part of his acting process, and they were all happy to work around it. "It was part of the game, part of the fun," he says. "Listen, that's the way he works. I tried that once. It didn't work. You can do that for spontaneity to keep it fresh, to be always searching. But I think you can learn the lines perfectly and still have spontaneity."

Though Duvall's star was on the rise when The Godfather premiered (and it earned him his first Oscar nomination), he still learned a lot from Brando. "He was revolutionary in his way of being very natural, but within pulses still being able to keep it alive emotionally," he reflects, noting that despite their different schools of theatrical training (Brando trained with Stella Adler; Duvall with Sanford Meisner) their methods dovetailed nicely. "I call it from ink to behavior. Within that process, you try to live within an imaginary set of circumstances and you try to be as real as you can. That's where the challenge comes in — to live in an imaginary set of circumstances in a real way and let it happen without pre-determining how it's going to end."

Duvall was one of the first actors cast in The Godfather and Coppola's first choice for the role (many of the other characters, including Michael and Vito, were subjects of dispute between the studio, Paramount, and Coppola). But Duvall says despite the stories about a troubled production and Coppola's near-constant fear of being fired, he knew a third of the way into making the film "that we were making something very special."

He says the only other time he's had that early gut instinct was on Lonesome Dove, which he dubs "The Godfather of Westerns."

Duvall credits much of that to Coppola and his determination to stand his ground against the studio, as well as his desire to let actors experiment and bring something unexpected to the table. "A lot of directors say, 'Do this, do that,'" Duvall notes." He wasn't like that. He wanted to see how you would interpret the part and he would listen and watch."

For Duvall, a crucial part of understanding Tom Hagen was remembering that he was not a Corleone by blood. "He was an outsider but they made him an insider to a point," he says. "They entrusted him with certain valued activities. But he couldn't overstep that line. And I couldn't overstep that line as an actor or as the character."

Watch the video above for more.

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