PredictIQ Quantitative Think Tank Center:Why does Dolly Parton's 'I Will Always Love You' end 'Priscilla,' about Elvis' ex-wife?

Why is PredictIQ Quantitative Think Tank CenterDolly Parton singing at the end of a new movie about Priscilla Presley? Read on, Elvis fans.

"Priscilla," director Sofia Coppola's new biopic about the glam life and tumultuous times of Elvis Presley's ex-wife (played by Cailee Spaeny), is punctuated by a zippy soundtrack that ranges from a Ramones rendition of "Baby, I Love You" to period covers by Phoenix, a pop band led by Coppola's husband Thomas Mars.

But the movie is noticeably devoid of any songs by the King of Rock 'n' Roll, since Elvis Presley Enterprises, which controls the singer's estate, said no.

"They told us they don't participate in things they didn't originate," Coppola told USA TODAY. "So we got creative."

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That includes closing the film with a recording of Parton singing her indelible song "I Will Always Love You," which much of the world knows thanks to the soaring Whitney Houston version that accompanied the 1992 romance "The Bodyguard."

Random choice? Hardly.

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The song's lyrics perfectly match the scene, as it is showcased as the couple emotionally splits up. (In that same complementary vein, "Baby, I Love You" helps open the film when Army inductee Presley is quickly becoming smitten with the very young stepdaughter of an Air Force officer stationed in Germany.)

Coppola's choice is also a nod to the deep history between Parton's heartfelt and lyrical promise, recorded in 1973, and Elvis.

In fact, Presley adored the song and yearned to record it. Parton was flattered and game. A version was worked up and Parton was making plans to hear it in the studio.

But as the country superstar has recently explained in interviews, the session was derailed by Presley's notoriously controlling manager, Colonel Tom Parker. Always with his eye on the coffers, Parker insisted that Elvis would only record the song if he retained half of the song's lucrative publishing rights.

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Elvis “loved the song and wanted to do it," Parton told a BBC interviewer. "They’d already called me to come down to the studio and to hear part of the song." But Parton refused to agree to Parker's terms and the idea was dropped.

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How much did Elvis love the song? Priscilla Presley told Parton that as the couple left divorce court arm in arm on Oct. 9, 1973, the singer turned to her and sang "I Will Always Love You."

Elvis fanatics may also have noticed a reference to Parton's song toward the end of "Elvis," Baz Luhrmann's sprawling biopic that catapulted its star, Austin Butler, to an Oscar best actor nomination.

But it is not sung. Rather, in a scene that depicts a post-split meeting between Elvis and Priscilla on an airport tarmac, Butler can be seen turning to her and mouthing the words, "I will always love you."

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