By Jean Lowerison

“Once upon a time” seldom works out in real life, but everybody loves the fantasy and keeps hoping. That may partially explain the crowd that jammed London streets to see the wedding procession of the Prince of Wales and Lady Diana Spencer in 1981.

But Diana’s fairy tale ended long before her death in 1997. It started to wilt shortly after the wedding, when 20-year-old Diana realized that she was in a three-way relationship: her 32-year-old prince was married to her but in love with the already-married Camilla Parker Bowles.

La Jolla Playhouse presents “Diana” through April 14 at the Mandell Weiss Theatre. Though billed as a new musical, “Diana” is really an opera with minimal dialogue. Joe DiPietro wrote the book; David Bryan the music. Both share creativity for the lyrics.

Diana didn’t really fit in with the stuffy British royal family, a fact she realized and accepted early on. Unlike them, she was pretty and friendly, and quickly became a media darling, even putting up with that annoyance gracefully (well portrayed in the song “Snap, Click”). She also did as expected, producing two royal heirs. But her relationship with Charles brought mostly heartbreak.

“Diana” portrays all of this, but focuses on how she reinvented herself by committing her time to charitable causes, thus bypassing the royal connection and coming into her own as an international force for good before that horrifying 1997 crash in Paris. She was one of few people who visited AIDS victims early in that crisis, even hugging and shaking hands with them barehanded.

To this, Charles sniffed “People are talking about your excessive devotion to ghoulish causes” – which only made Diana all the more determined.

The play skips around rather more than seems necessary, and even includes romance novelist (and Diana favorite) Barbara Cartland for no apparent reason, though she is played with amusing relish by Judy Kaye, all fluffy in pink. Kaye is also excellent as the more matter-of-fact Queen Elizabeth, exuding all due sniffiness and lack of charm.

The show has a Broadway look, with lots of set changes and bright lighting that shines out into the audience. Ian Eisendrath’s nine-member orchestra acquits itself well on the ’80s-inspired songs, and choreographer Kelly Devine provides energy galore with some athletic dance numbers for a large ensemble. Natasha Katz’s lighting and Gareth Owen’s sound design shine especially in these numbers.

Jeanna de Waal is terrific as Diana – beautiful, charming, and as warm and personable as Charles (an excellent Roe Hartrampf) is cold and distant.

Erin Davie plays the unattractive role of Camilla with as much style as can be managed (especially in the ultimate boxing match face-off scene with Diana to the song “The Show”).

William Ivey Long’s costumes are marvelous, especially the sexy one late in the show when Diana sings “The Dress.” Here, she has finally abandoned royalty and come into her own, symbolized by the words “f-xxx-it” inserted between the title words.

DiPietro and Bryan, who won Tonys for the music of “Memphis,” have given “Diana” a mostly jaunty, upbeat, ’80s-inflected score that serves the choreography well but is less effective for the narrative. The lyrics of the fast songs (and that’s at least 80 percent of the score) are often unintelligible, and many of them sound alike. Perhaps they’d be better understood as dialogue.

“Diana” is a certified draw, attested by the fact that this show has been extended twice and it’s only in its first week. With a few tweaks in the music, this committed cast can give this show a long life.

— Jean Lowerison is a long-standing member of the San Diego Theatre Critics Circle and can be reached at [email protected].