More than 40 years after Elvis Presley’s death, a documentary backed by his former wife, Priscilla, will chart the singer’s early life as a young man from Tupelo, Mississippi.

A two-part, three-hour HBO documentary, Elvis Presley: The Searcher, will be broadcast in the US this month. It has been backed by the Presley estate, in the hope that it will re-focus attention on Presley’s captivating music and presence, as opposed to his sad physical decline. The Searcher portrays the young Elvis as an “eclectic” music lover who, before making his first recordings at Sun Studio, was slipping into the black clubs on Beale Street in Memphis, or into the black gospel churches, to assemble “his version of himself”.

“We didn’t exactly know who he was but there weren’t a lot of white kids hanging out at the clubs,” renowned Stax Records producer David Porter told the Observer.

Long before Sam Phillips invited the young singer to cut his first tracks, Elvis was a familiar figure on Beale Street, absorbing the musical style that came to be known as Memphis blues, says Porter. “He wasn’t there to party, he wasn’t there to be a fly on the wall. He would come down to the Flamingo Room to observe singers like Rufus Thomas, Jackie Wilson and Roy Hamilton.”

Priscilla Presley says the documentary, which took more than six years to complete, is “an honest effort to get the story straight about who he was.”

“There have been so many documentaries and so much that has been shown on film already. There are so many different perceptions, so many different people’s ideas, so much altered information and so many questions,” she said. She describes her own involvement as the first time she has let her guard down about her former husband. “It’s still hard for me to watch after living it because so much went down,” she says.

Much as Martin Scorsese’s documentary Living in the Material World burnished the reputation of George Harrison, the makers of The Searcher believe the time is right to return to a focus on Presley’s music and his ability to connect with an audience.

Director Thom Zimny says his effort was to reveal a man driven by music “even at his darkest times”. Zimny told Rolling Stone last week: “I wanted to attack and shatter the shorthand version of Elvis Presley’s life story – that after the army there was just bad films, bad recordings, bad tours and then his life was over.”

Despite backing the project, Priscilla Presley says she is anxious that Elvis fans might not want to see their idol this way.

“They know him as a movie star, the king of rock’n’roll, and now we’re exposing what went on behind the scenes. Do they want that image taken away? But if you truly love him, then you want to see him this way.”

Facebook Twitter Pinterest Elvis in the front yard of his home at 1034 Audubon Drive, Memphis in 1956. Photograph: The Elvis Presley Estate/Reuters

Part of the filmmakers’ focus is to look at what is commonly known as the Elvis Presley ’68 Comeback Special, the TV show that reclaimed Elvis as a musician after seven years of making lightweight, music-focused Hollywood films under the direction of his manager, Colonel Tom Parker, who many hold responsible for failing to put Elvis together with producers who could have pushed him creatively.

“The ’68 Special came at the right time, it brought him back to what he loved most, which was performing,” Priscilla recalls. “Elvis was so nervous before he went on. He didn’t want to come out of his dressing room. We were all so young at the time, we didn’t always know what he needed. He was like a young boy sometimes. At the time, we didn’t realise how great he was.”

She was just 14 when she met the singer during his military service in Germany, but didn’t start dating Elvis, who was a decade older, until he returned to Memphis after he was discharged.

The second part of the documentary deals with Elvis in the later years, his declining health, punishing touring schedule and reliance on prescription drugs, and one final, epic recording session in Graceland’s Jungle Room a year before he died.

“It was difficult for all of us, we certainly didn’t see it coming,” Priscilla says of Elvis’s sad decline. “But we certainly saw the journey he was taking.

“People go, well, ‘Why didn’t anyone do anything?’ Well, that’s not true. People there in the inner group did, but you did not tell Elvis Presley what to do. You did not. I mean, you’d be out of there faster than a scratched cat. They would try and no way. He knew what he was doing.”

• An incorrect reference to Nashville as the location of Sun Studio, Memphis, was deleted on 10 April 2018.

