One of the reasons "Forrest Gump" is a cherished movie is because of the way it lightheartedly traverses decades of key moments in U.S. history and popular culture through the eyes of an altruistic titular protagonist, Forrest Gump (Tom Hanks) — inspired by a couple of real-life blokes. In the eyes of the film, even one simple person can make a big impact on the world around them. The film cleverly blends these events with a fictional narrative to show the significance of Forrest's actions.

In "Forrest Gump," during Alabama Governor George Wallace's 1963 "Stand in the Schoolhouse Door" event where he protested the de-segregation of schools, Forrest curiously watches from the crowd and then helps African-American student Vivian Malone when she drops her books on her way into the school.

Later, during an appearance alongside John Lennon on "The Dick Cavett Show," Forrest inspires the lyrics to Lennon's best-selling single "Imagine." And he would visit John F. Kennedy at The White House just weeks before the President's assassination.

More humorously, the film posited that Forrest was the one responsible for calling security about the Watergate scandal, at Richard Nixon's doing. Forrest's mud-covered face is responsible for the smiley face logo all over t-shirts and stickers.

Oh, and in a chance encounter with Elvis Presley, Forrest taught the King of Rock and Roll how to dance — how can we forget that. And even though we don't see him in "Forrest Gump," it was yet another opportunity for Kurt Russell to portray Elvis Presley on the big screen.

It Took Two Men To Play Elvis

In the film's narrative, Forrest Gump (Michael Conner Humphreys) spent much of his early childhood in unwieldy leg braces as the result of a crooked spine. At one point, his mother Mrs. Gump (Sally Field) had taken to renting out rooms in their home for extra money. As Forrest would tell us, "There was always folks coming and going … One time, a young man was staying with us, and he had [with] him a guitar case."

That young man, of course, was Elvis Presley. In the film, Elvis shows Forrest "a thing or two on the guitar." Because of his leg braces, Forrest could only dance by shaking his hips as best he could. After Elvis saw him dance, he asked Forrest to "show [him] that crazy little walk you did there." Forrest obliged while Elvis sang "Hound Dog." Director Robert Zemeckis cleverly hides Peter Dobson, who plays Elvis, either out of focus in the background or by filming him from behind.

It wasn't until years later that people would learn that Zemeckis hid Dobson from us in a totally different way. Although it was Dobson on screen as Elvis, audiences were hearing someone entirely different. Zemeckis even left Elvis' voice actor off the "Forrest Gump" credits. It was a secret that was kept hidden for decades.

Nobody Knew It Was Kurt Russell's Voice

Kurt Russell's connection to Elvis Presley began tangibly. The "Escape from New York" star made his feature film debut — albeit uncredited, just as with "Forrest Gump" — in 1963's "It Happened at the World's Fair" starring none other than Elvis. And then in 1979, two years after Elvis's death, Russell portrayed the musical icon in John Carpenter's made-for-TV movie, "Elvis."

But there's a lesser-known Elvis appearance — if you can even call it that — in Russell's filmography: "Forrest Gump." The Elvis in the Tom Hanks-led film is an amalgamation of Dobson (providing the body) and Russell (offering the voice).

While Russell's involvement had long been a rumor, the actor finally confirmed it in a 2016 interview with GQ. And much like Elvis steals Forrest's dance moves in "Forrest Gump," Russell sort of stole the voice from Dobson:

"I did that as a thing for [director Robert Zemeckis]. He didn't like what it was and said, 'I need something real bad.' I didn't know if, to be honest with you, [Zemeckis] was doing it on the sly. In other words, the actor didn't know. It was fun to do."

Though it wasn't planned, his performance as Elvis in "Forrest Gump" continues to make Russell one of the most convincing Elvis actors in Hollywood. Even when we don't know about it.

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