We begin with the ending of “La La Land” (and this is giving nothing away), because the ending is like a brilliant short film unto itself — beautiful and heart-stopping and bold and different and wow.

So many movies, even many of the good ones, end with a predictable flourish, whether it’s the climactic battle sequence followed by a brief epilogue; the grand romantic gesture topped off with a callback to a running joke; the wounded hero or Lone Survivor sitting on the bed of the ambulance or the fire truck with a blanket wrapped around the shoulders; or the obligatory soaring camera pulling up, up and away from the final scene, until we have a bird’s eye view of the entire city.

“La La Land” writer-director Damien Chazelle (“Whiplash”) is a blazing talent, and in the final act of this exhilarating, energized, beautiful and stylized song-and-dance homage to the great studio musicals of the 1940s and 1950s, we are blown away by a sequence we will always think of, always see in our mind’s eye, when we think of this movie.

The frequently paired Ryan Gosling and Emma Stone deliver genuine movie-star turns as Sebastian and Mia, two struggling aspiring artists — he a jazz musician, she an actress — who would be considered young in just about any universe outside of Hollywood, but find themselves running out of time against the unforgiving ticking clock of showbiz that says if you haven’t made it after a few years, you might as well go home.

“La La Land” is set in the present day, but it often seems to be taking place in another era. The dapper Sebastian favors earth-tone suits and ties of brown and gold, while Mia steps out in a dress of such bright yellow it would shame the sunrise.

As they meet cute and then meet cute again and begin the classic courtship of verbal fencing that leads to tentative gestures of affection that leads to … well, you know how the song goes, Sebastian and Mia often break into song or engage in delightfully choreographed dance numbers, as the “real world” fades into the background and we are welcomed into a dreamlike fantasy.

“La La Land” opens with a huge splash, an elaborate production number titled “Another Day of Sun,” set in the middle of a seemingly endless traffic jam on the freeway. (One can easily envision the Broadway version of this number if and when “La La Land” makes the popular movie-to-stage transition.) It’s an incredibly ambitious sequence featuring dozens of performers executing a series of singing and dancing handoffs with the grace and skill of an Olympic relay team.

From that great big opener, “La La Land” effortlessly transitions to a more intimate, character-driven scope.

Mia works as a barista on a studio lot. It’s the ultimate in nose-pressed-to-the-window employment, for Mia finds herself serving coffee to movie stars and catching glimpses of Hollywood literally just outside the door, and she’s often scurrying out of work to race to another audition — but at the end of the day, when it’s clear the casting directors will be “going in another direction,” Mia is surrounded by reminders it hasn’t exactly worked out since she left home years ago with stars in her eyes.

Meanwhile, the keyboard purist Sebastian stubbornly clings to his dream of opening an old-school jazz joint — but he has to make ends meet by plinking out milquetoast standards in lounges and playing in cheesy 1980s cover bands.

And then, at just right moment (or is it just the wrong moment?), Sebastian and Mia fall in love, and Los Angeles reveals itself to be a glorious, fantastic, Cinemascope landscape — a star-filled canvas on which the dashing leading man and the lovely leading lady can paint their love story.

Emma and Ryan won’t make you forget Fred and Ginger. They’re quite good, but it feels a little bit as if they’re the best contestants in the history of “Dancing with the Stars” and not in the same league as the magical dance duos of an era gone by.

That’s OK. The songs and score from Justin Hurwitz (with lyrics by Pasek and Paul) carry the day.

Chazelle’s script is hopeful and sweet and clever and rich. His direction is innovative and captivating. Linus Sandgren’s cinematography is Oscar-level.

Gosling and Stone are magical together. J.K. Simmons and Rosemarie DeWitt lend their grace and presence to minor but memorable roles. John Legend manages to make us forget he’s John Legend as Sebastian’s former music partner, who offers Sebastian a devil’s ransom to compromise his musical beliefs.

There’s been so much film festival and critical hype about “La La Land” for so long. Forget all that. It’s not going to change your life. It’s not the reinvention of the movie musical.

It’s simply wonderful.

★★★★

Summit Entertainment presents a film written and directed by Damien Chazelle. Rated PG-13 (for some language). Running time: 128 minutes. Opens Friday at local theaters.