Elvis Presley 'Regretted' Not Doing Barbra Streisand's A Star Is Born, Says Priscilla (Exclusive)

Elvis Presley almost starred in 1976's A Star Is Born.

Barbra Streisand initially had the King of Rock 'n' Roll in mind to play her onscreen love interest in the film, but Elvis' manager Colonel Tom Parker told him not to take the role. The part ultimately went to Kris Kristofferson.

"Barbra had offered him the part," Elvis' ex-wife Priscilla recalls to PEOPLE. "Colonel talked him out of that saying, 'Oh, it's not going to be good. She's going to be in charge, not you. Her movie, not yours.' Elvis regretted that because he felt he could have played that part."

Elvis' complicated dynamic with Parker is explored in the new Netflix documentary Return of the King: The Fall and Rise of Elvis Presley (streaming now). The film looks back on how Parker got Elvis locked into an multi-year movie contract following his return from the Army in 1960.

Over time, Elvis became increasingly frustrated with the scripts he was being presented.

"One day he was reading a script, and he threw it across the room and said, ‘I’m not doing this,’” says his longtime friend Jerry Schilling. “The Colonel loved Elvis and vice versa, but Elvis outgrew the Colonel.”

Priscilla, 79, says he "wanted to be in great movies, not the stupid movies that he did like Girls! Girls! Girls! That wasn't Elvis."

"Colonel did not get him really at all," she says. "That was hard for both Jerry and I, but you couldn't say anything to Colonel. You just had to keep quiet."

Schilling adds that Elvis "called James Dean a genius, and he loved Marlon Brando." Following Dean's death at age 24 in 1955, Schilling says Parker approached producer Hal Wallis about Elvis taking Dean's part in 1958's King Creole.

"Colonel went to Hal and said, 'What about Elvis for this movie?'" Schilling says. "Because Elvis really wanted those type of movies. Hal went to Michael Curtiz, the director, and he said, 'No Elvis.' Hal and the Colonel said, 'Why don't you just have lunch, just meet with him?' Michael fell in love with Elvis as an actor. At the end of that picture, it was his fourth, Elvis walked over to Michael and said, 'Thank you, Mr. Curtiz. Now I understand what a director is.'"

The movie roles that followed King Creole were less creatively fulfilling to Elvis, but he was able to breathe new life into his career with his '68 Comeback Special that aired on NBC on Dec. 3, 1968.

Though Parker tried to get him to do a family-friendly Christmas special, Elvis insisted on a return to his rock roots.

"The Colonel, he came from the old school where he wanted Elvis to be Bing Crosby doing a Christmas Special, rather than doing a sexy rock and roll gospel, like the '68 special," says Schilling.

The special went on to become the highest-rated show of the year for NBC. Elvis dedicated himself to live performances from then on, and he played hundreds more concerts before his death at age 42 in 1977.

"I feel strongly I lost my friend at an early age out of creative disappointment. I know I did," says Schilling. "That creative disappointment caused other problems. But when he had a challenge like the '68 Special, he would go into training like Muhammad Ali. He'd lose 20 lbs."