NEW YORK — “Elvis & Nixon” (opening Friday), with Kevin Spacey as the 37th president and Michael Shannon as “the King of Rock ‘n’ Roll,” is based on that infamous 1970 photo of President Richard Nixon and Elvis Presley — reportedly the most requested reprint at the National Archives.

The bizarre meeting between the two men was initiated by Presley, who literally showed up at a gate to the White House without an appointment to offer his services as an undercover “federal agent-at-large.” Presley’s apparent intent was to aid in the fight against illegal drugs and attempt to help the president restore youth’s faith in America’s historic mission.

Today politics and entertainment are somewhat blurred, in the sense political leaders — even presidents — are totally aware of the impact entertainment figures have on our popular culture. “Elvis & Nixon” showcases how that was far from the truth in 1970 — especially in a White House run by a man who had little interest in the world of show business.

As Spacey noted, Nixon “didn’t have an interest in meeting Elvis Presley. [Top Nixon aide H.R.] Haldeman didn’t have an interest. They didn’t see any political value in meeting Elvis. And yet, that’s one of the things about the journey of this movie. By circumstance these two individuals come together, maybe not thinking they’re going to have a sympathetic understanding of each other.

“But then, by the end of it, they really do having an understanding and appreciation of each other. They actually enjoyed each other. That’s certainly what we tried to get across in the film.”

President Richard Nixon and Elvis Presley at the White House, December, 1970. | National Archives

President Richard Nixon and Elvis Presley at the White House, December, 1970. | National Archives

If Spacey could have met Nixon, the two-time Oscar winner said he would have been intrigued to not only observe the man, but to ask him a question about the path he chose in life.

“He was such an interesting figure and had such a difficult life in his early years. Yet, he somehow pulled himself out of that, but went into a profession that seems — from everyone that knew him and talked about him — completely the antithesis to the kind of person he was.

“He wasn’t outgoing. He wasn’t gregarious. He didn’t feel comfortable around people. I suppose that would be one of the questions I’d ask him: ‘Why? What compelled you to do something that is so clearly something that makes you feel awkward and uncomfortable?’ ”

A new film tells the behind-the-scenes story of how the King of Rock and Roll met Richard Nixon in the Oval Office. The 1970 photo of Elvis Presley shaking hands with the president is the most requested photo from the National Archive.  Elvis & Nixon deta

Both Shannon and Spacey have carved out award-winning and critically acclaimed careers as stage actors,  along with their achievements in film. “I suspect that Michael and I both have such affection for what doing theater means,” Spacey said. “It teaches you about storytelling and teaches you about creating character and having an arc of a character that is clearly defined. In the theater you get such a remarkable experience of being able to go from A to Z — in other words you do it chronologically.”

It’s often just the opposite when it comes to shooting a film. “In movies you might start out shooting scene ‘L,’ and then a few weeks later you shoot scene ‘S.’  It’s almost always very much out of order.”

“Elvis & Nixon” had both longtime Presley friend Jerry Schilling and former top Nixon aide Egil “Bud” Krogh involved in the film and used material from both men’s books related to this famous meeting.

The first time Krogh saw Spacey on the set, in full get-up as Nixon, “I really think he was having a little seizure,” the actor said.

“He doubled over and grabbed his stomach. For him, it was as if Nixon had come back to life and was in the room. I took that as a great compliment to my makeup and hair team who organized my look.”

While Spacey is well-known as one of Hollywood’s best impressionists of various famous figures — ranging from Jack Lemmon to Johnny Carson — he went about researching Nixon in a very specific way.

“What I found helpful was the documentary ‘Our Nixon,’ that included a lot of home movie footage taken by White House staff members. It was footage no one had seen before in public.

“I found that more helpful than looking at Nixon in public circumstances, because what we were doing in this film was showing such a private meeting. That was the stuff I was interested in. I wanted to see what he was like in private, behind closed doors.

“One thing I learned: He definitely swore a lot!”