Cailee Spaeny and Jacob Elordi in A24's Priscilla.

The dramatic height difference between the leads accomplishes a great deal of work in “Priscilla,” visually conveying the power disparity between superstar Elvis Presley and Priscilla Beaulieu, who he began wooing when she was just 14. Unfortunately, writer-director Sofia Coppola’s version of this oft-told story moves at a snail’s pace, offering fine performances but little to set one’s soul – or anything else – on fire.

At 5’1”, Cailee Spaeny, who plays Priscilla Presley in this adaptation of her autobiography, stands a few inches shorter than her alter ego, while the 6’5” Jacob Elordi (“Euphoria”), a full five inches taller than Elvis, towers above her.

That gap proves particularly striking in the early going, when Priscilla, a teenage army brat with her dad stationed in Germany in 1959, meets the then-serving Elvis, whose interest in her leaves her parents with understandably suspicious minds.

Starstruck and naive, Priscilla becomes something of a zombie when Elvis returns to the states, thinking she’s been forgotten before he summons her to Graceland, somehow convincing her folks to let her finish high school there.

Gradually, the roots of his infatuation with someone so young become clearer, reflecting a desire in the wake of his mother’s death to exercise complete control over her, from her hair to her clothes to having her wait around the house during his movie shoots. He even begins sharing pills with her, assuming she needs the same assistance to pep up or sleep that he does.

Spaeny nicely conveys Priscilla’s mix of infatuation and confusion, the latter stoked by Elvis’ reluctance to advance their physical involvement. Ditto for Elordi in mimicking Elvis’ polite mumble and especially his boisterous laugh, in a role much narrower in scope than Austin Butler’s Oscar-nominated turn in the recent “Elvis.”

Cailee Spaeny as Priscilla Presley in director Sofia Coppola's "Priscilla."

The story, however, advances sluggishly, extensively focusing on an early period in their relationship where not much happens. At times, the movie’s literally as exciting as seeing the two sit in bed together watching “The Beverly Hillbillies” or Johnny Carson.

“Priscilla” eventually gets into juicier, more conflict-driven territory – like Elvis assuring her that nothing happened with Ann-Margret during the making of “Viva, Las Vegas,” the tabloid headlines notwithstanding – but by then it all feels like too little, too late. Convincingly aging the central duo, the film glosses over intriguing aspects of Elvis’ career, such as his admiration for Marlon Brando and James Dean and desire to stretch beyond the awful scripts sent his way.

Denied access to Presley’s songs, Coppola does make especially good use of period songs by other artists to set the mood, with Tommy James’ “Crimson and Clover” playing as Priscilla sleepwalks through school after her first tender brush with rock ‘n roll royalty.

Ultimately, though, “Priscilla” fleshes out her side of things while getting lost somewhere in the abundant filmography of movies and TV devoted to Elvis’ life and legend, adding details to Priscilla’s experience without significantly enhancing an understanding of either of the principals.

That’s not to say the movie lacks merit (more likely to be appreciated on some streaming platform), only that as opposed to headlining the main stage, it feels like an opening act, caught in a trap of its own limitations.

“Priscilla” premieres October 27 in select cities and November 3 in wide release in the US. It’s rated R.