The enormous success of “Bohemian Rhapsody” might lead you to expect much of Dexter Fletcher’s biographical movie about Elton John. After all, he was the fellow called in to complete the Freddie Mercury picture after Bryan Singer was removed from the director’s chair, and some credit him with having saved the project.

But “Rocketman” is very different from the conventional, old-fashioned but expertly mounted musical biography that “Rhapsody” was. It’s basically a musical psychotherapy session, and it’s not nearly as much fun. Its rather slapdash narrative and visual qualities also suggest that Fletcher’s contribution to the earlier film have been wildly overstated.

The structure of Lee Hall’s script is announced at the very start as a garishly costumed John (Taron Egerton) stalks into a group therapy session, admits his addictions, and is prodded to tell his story. His memories take him back to his childhood, when as a boy (played first by Matthew Illesley and then by Kit Connor), he suffered as a result of his parents’ attitudes, with his mother (Bryce Dallas Howard) dismissive and his disciplinarian father (Steven Mackintosh) positively hostile. But young Reggie showed instinctive ability at the keyboard, and with the support of his genial grandmother (Gemma Jones), his only source of affection in the household, won a scholarship to the Royal Academy.

His reminiscences continue into his stint as a local pub pianist and leader of a band called Bluesology, during which he experienced a confused sexual awakening. It was also through a meeting with record exec Ray Williams (Charlie Rowe) that John was introduced to Bernie Taupin (Jamie Bell), who became his lyricist and best friend. It seems like no time at all passes before Williams’ tough-talking boss (Stephen Graham) lines up a slot for John at Hollywood’s famous Troubadour, where he’s welcomed effusively by manager Doug Weston (Tate Donovan) and has a sensational American debut.

That’s also the occasion of his meeting with John Reid (Richard Madden), who becomes Elton’s lover as well as his manager. He takes the singer to stratospheric heights of success, but is depicted as a slick manipulator who also takes him into a life of dissipation that leads him to a rupture with the ever-loyal Taupin, a brief marriage, confrontations with his remarried mother and father, and even a suicide attempt. It’s only afterward that John stalks off a gig at Radio City Music Hall to go into rehab, bringing the film full circle; as we’re told before the credits roll, he cleans up his act, finds his life partner, becomes a philanthropist and builds a long and illustrious career.

This typical trajectory of rise-fall-rise is told, in effect, via fantasy flashbacks as John continues his therapy session; these not only juggle the facts considerably (as pop music scholars will certainly explain in detail), but take the form of dreamlike performances of John’s songs, which are used to comment on the action of the moment. “Rocketman” is thus a sort of jukebox musical in the form of a partial biography, told entirely from John’s perspective, in the ultra-flamboyant style that’s become his trademark. And by spending so much time on his descent into excess, it aims to be seen as what amounts to a brave self-portrait.

In actuality, though, the picture ends up, as one might expect of an “authorized” project (executive produced by John himself), a rather smug depiction of John’s triumph over the personal adversity that he struggled with even as he achieved fame. And what is the key to understanding the singer’s underlying unhappiness? It is, of course, the lack of the love he so desperately needed, a love his parents denied him. Taupin says he loves him, but as a brother, not in the physical way John needs. Reid effectively seduces him, but the cold, calculating way in which he uses him is certainly not the stuff of genuine love. It’s only after his renewal through therapy, when he meets the man who’s his true soul mate, that John feels fulfilled. And so though “Rocketman” is chockfull of Elton John’s songs, its true message is that of one by other hands—“All You Need is Love.” That’s an even more bluntly obvious version of Rosebud than Charles Foster Kane’s was, made more so when the main characters from his recollections are shown confronting him in his therapy session.

The please-like-me quality of the story being told here is also reflected in Egerton’s performance. It will certainly win wide praise—Egerton put on a few pounds to play the part, does his own singing (and quite well), and dances adequately. But it’s a very effortful turn, one that constantly makes you aware that you’re watching an actor who isn’t terribly charismatic trying very hard to seem that he is. The result might remind one of the (perhaps apocryphal) remark that Heath Ledger is supposed to have made when he lost the Best Actor Oscar (for “Brokeback Mountain”) to Philip Seymour Hoffman (for “Capote”)—“I thought it was for the best acting, not the most acting.” Egerton screws up his face, puffs out his cheeks, shouts and scowls (always before apologizing)—one of the worst examples coming in the phone call to his mother when he finally tells her he’s gay)—but the result never feels true; it’s acting of the old Jon Lovitz Saturday Night Live school.

Among the rest of the cast, only Bell offers a performance that captures a genuine person. Everyone else offer turns that are highly stylized, reflective of the fantastical spin Hall and Fletcher put onto the entire narrative. Unfortunately, neither Fletcher nor his colleagues, cinematographer George Richmond and editor Chris Dickens, have quite the skill to pull it off. They don’t ruin the glitzy but impressive period creations of production designer Marcus Rowland and costumer Julian Day, but their erratic work does undermine the efforts of choreographer Adam Murray, whose dance routines are chopped and diced excessively.

While “Rocketman” disappoints in many respects, however, it does offer a cavalcade of many of John’s greatest hits—even if in attenuated form and incongruous context—and for fans of the singer that may be enough.