Down the bumper-to-bumper streets of La La Land — the titular and musically catchy nickname for L.A. — someone in the crowd jumps out and bursts into song to “Another Day of Sun.” A boy honks at a girl, and that same girl flips off the boy. It’s a perfect day for a chance at romance in the city of stars.

The girl, Mia (Emma Stone), a budding actress who’s endured years of play practice and effete callbacks that never were, is trying to make her long-lived dream come true in the one city where dreams are palpably possible. The guy, Sebastian (Ryan Gosling), or Seb, is an ambitious jazz musician who flirts with the idea of turning a loathsome samba and tapas place into an evocative jazz club  — one where anyone, not just Hoagy Carmichael enthusiasts, can sit and enjoy the nostalgic magic of jazz. Put a cigarette in his mouth and you’ve got Humphrey Bogart.

Life goes on as usual until Mia and Sebastian have another one of their chance encounters. Our heroine reverts to coffee, auditions and Hollywood parties that only make her feel like “Someone in the Crowd.” Late at night, she encounters Seb at a dim-lit restaurant playing piano to the song (“Mia and Sebastian’s Theme”) that would soon win her heart and beg a tap dance.

With Seb’s vintage features and vinyl, this movie is a millennial’s love letter, propagating the once-unpopular idea that you can have both classicism and modernity in life. Its two main actors, Stone and Gosling — who have also appeared side-by-side in “Crazy, Stupid, Love” and “Gangster Squad” — give off a sensational spark of an old-movie couple, one that this generation has been wrongfully deprived of.

But let’s not forget the prodigy himself: director Damien Chazelle, who stunned Hollywood with a masterpiece that won seven Golden Globe awards and got nominated for a whopping 14 Oscars. It’s no wonder that “La La Land” came out on top for Best Original Score in particular; the movie features Justin Hurwitz’s soundtrack composed upon galaxies and happily ever-afters. Only through such music is the audience able to experience the exhilaration of chasing dreams, something that no longer belongs solely to old-fashioned idealists.

But all those songs didn’t come easy.

“I practiced some of those piano pieces four hours a day for three months. I should never want to hear them again, but I’m still moved by them,” Gosling said in an interview. Believe it or not, Gosling actually performed all the up-close-and-personal piano scenes for Chazelle’s image of authenticity.

This picture is one for surrealists and careerists, for “the fools who dream (crazy as they may seem)” and for nostalgia junkies: The film’s colorful yet retrospective on-screen performances will make you feel bigger than life. Shot through the brilliance of cinemascope, the beautifully sunny L.A. days and glitterish L.A. nights only become more irresistible. Especially noteworthy is the scene where Seb pays homage to “Rebel Without a Cause” by driving Mia to a night under the stars in the Griffith Observatory, then waltzing her off the ground into the limitless universe of love.

In an unforgiving world where dreams seldom see the light of day, caught behind reality’s demanding restraints, Seb is here to say, “This is the dream! It’s conflict and it’s compromise, and it’s very, very exciting!”