In 1972 Gianni Russo was approaching 30, and had zero acting experience, when he literally got the job of a lifetime.

He was offered the role of Carlo Rizzi, the wife-beating, double-crossing son-in-law in Francis Ford Coppola’s epic mob drama “The Godfather,” which starred Al Pacino, Robert Duvall, James Caan and Marlon Brando as Vito Corleone — and went on to be acclaimed as one of the best films of an era.

Russo recently chronicled his rise to stardom and the many shocking turns of events that occurred along the way in a new memoir titled “Hollywood Godfather.” In the book, Russo describes how he did screen tests playing Michael Corleone, Sonny Corleone and then Rizzi before getting the role.

On the set of "The Godfather," baptism day, (L to R) Gianni Russo, Al Pacino and director Francis Ford Coppola. (Private collection of Gianni Russo)

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But not everyone was easily impressed by Russo’s luck.

“It was very funny because [Brando] said, ‘You have a big movie coming out?’ and I said 'No,'” Russo recalled to Fox News on how the film’s leading star believed Russo must have been well established in Hollywood to receive such a gig.

“He goes, ‘You’re a TV actor?’ I said 'No,'” continued Russo. “He goes, ‘You’re not on Broadway? I know everybody on Broadway.’ I said, ‘You’re right.’ He says, ‘Who did you study with?’ I said, ‘Study what?’ And he called Francis Ford Coppola over, the director, and I didn’t know protocol because I was never on a set. So Francis comes over and he starts breaking down the whole script with me… [Brando] says, ‘He’s got to be a great actor. You got to rethink it.’ And I’m saying to myself, ‘Wait a minute. I just told everybody I’m doing this part. They all didn’t believe me to begin with. Now this guy’s going to get me fired?'"

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Marlon Brando during a scene in "The Godfather." (Getty)

Russo quickly dismissed Coppola and committed what he called “the next sacrilege.”

“I put my arm on Brando and I walked him out of earshot of everybody else,” said Russo. “I turned him around and I said, ‘Let me just tell you something. You screw this up for me, you hear what I’m telling you, I will suck on your heart. I told everybody I had this part. Why would you destroy this for me?’ And he stepped back. He said, ‘That was good. That was great acting.’ He thought I was acting! I meant it, and that was it. We were friends ever since.”

Fortunately for Russo, it was smooth sailing from then on. Not only did the cast get along, but they were eager to play practical jokes on each other when cameras stopped rolling.

“The biggest thing was the mooning,” said Russo. “There was a big contest of who could moon the most people at one time. And I’m saying to myself, ‘Are these people nuts? They are grown adults. They’re going to moon people.’ … At my wedding scene, [Brando] says, ‘We’ll wait for Michael,’ and there were 300 extras, all the crew — so it was like 500 people there. And then as you turned around, he mooned them all, even little kids, where I felt so bad. They’re looking at this old man’s ass. I mean, what is he crazy? But he won the contest.”

James Caan knocks out Gianni Russo in a scene from the film "The Godfather," 1972. (Getty)

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And it was his role in “The Godfather” that some years later would save Russo’s life, for real.

In 1988, a member of the Medellin drug cartel was reportedly harassing a female patron at his Las Vegas club and casino, Gianni Russo’s State Street, and Russo tried to intervene when the man attacked him with a broken Cristal bottle, slicing his chin.

“I had 180 stitches," said Russo. "My chin was hanging."

It was then that Russo pulled out a handgun and fired two bullets into his head.

"Fortunately, I always carry a gun, legally, explained Russo. "He got a little stupid, so I put the gun between his eyes. I said, 'This is it.' He said, "Oh yeah? F--- you.' I said 'OK.' I put two right in his head. He stood there. There was a hole in his head and he's looking at me... like a mosquito hit him. I found out from the coroner he was so high on coke, it took a second or two for it to register, but I’ll tell you, it’s the longest second or two you ever want to have in your life."

Gianni Russo, seated on the black Ferrari parked in front his State Street Club, poses for the album cover art, "Live from State Street." (Private collection of Gianni Russo)

The Clark County prosecutor ruled the killing a justifiable homicide, The New York Times reported. However, Russo claimed he had mob boss John Gotti arrange a meeting in Bogota, Colombia with drug lord Pablo Escobar, who was eager to murder his family in retaliation. Gotti, who reportedly disliked Russo, was nonetheless willing to make the meeting happen, the actor said.

"John and I really never got along," said Russo. "I guess he figured I'll never come back. 'Let him go, I'll set it up.' And that's how I got there."

When Russo finally arrived in Colombia, he claimed to be “roughened up” by the kingpin’s men before Escobar himself walked in, carrying “The Making of the Godfather.”

A mugshot taken by the regional Colombia control agency in Medellín in 1977. (Courtesy of Gianni Russo)

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“I thought I was hallucinating,” said Russo. “He said, ‘Why didn’t you tell me you were Carlo in ‘The Godfather’? That’s my favorite movie.’”

Russo claimed Escobar let him go — in exchange for re-enacting one of the scenes in “The Godfather.” Escobar played Michael Corleone.

“He knew the entire scene,” said Russo. “But I thought I was dead. He thought it was amazing courage for me to fly down to Bogota. So he straightened everything out.”

(L to R foreground) On the wedding set of "The Godfather," one of Joe Columbo's enforcers (seated), Richard Conte and Gianni Russo (standing.) (Private collection of Gianni Russo)

Thankfully for Russo, he had an easier time getting singing lessons from Frank Sinatra — even if it meant getting out of his comfort zone.

“I was going to get a singing lesson, so he says to me, ‘Did you bring a bathing suit?’” recalled Russo. “I said no. He says, ‘Well, go in the back of the cabana and get a bathing suit and I’ll meet you at the pool.’ I’m saying to myself, ‘I didn’t come here to swim.’ And so, he comes out and says, ‘Submerge yourself in the pool and stay down for as long as you can.’ And he’s timing me… After a couple of times, he kept timing me and going, ‘Do it again.’ I say, ‘Frank, I don’t understand. What’s this lesson?’ He says, ‘Breathing is everything. You’ve got to expand your lungs so you could retain the notes.’ For the whole week, that’s what we did.”

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Russo, who is 75 years old today, has starred in over 40 films, as well as recorded music dedicated to Sinatra and Dean Martin. He also serves as a motivational speaker where he encourages others to pursue their dreams, even if they seem unlikely.

“You have to get up and do something,” he said. “… I don’t care what your background is. Pick something you want to do, believe in yourself, go do it and it’ll happen. That’s why I did it.”