The Los Angeles Philharmonic took a major step forward over the weekend with its “Reel Change” series devoted to contemporary film composers.

By inviting Icelandic composer Hildur Guðnadóttir (“Joker”) and Americans Kris Bowers (“Green Book”) and Nicholas Britell (“Moonlight”) to curate programs of their music, and those of composers that inspired them, the Phil is formally acknowledging the importance of media music as a legitimate part of the contemporary musical scene.

Symphony programmers are notorious for ignoring film music unless it’s on a “pops” program or a live-to-picture event, which in recent years have proven extremely lucrative. The L.A. Phil has rarely programmed, much less celebrated, music for visual media on a subscription concert.

And the fact that the series included a woman and a person of color was more than a token nod to diversity, as this trio is among the most sought-after of modern composers for film, TV and games – and all have been active in concert music as well.

It is as if America’s finest orchestra has finally embraced the 20th-century British concept of a “working composer,” someone who shifted quickly and effortlessly from music for the concert hall to music for a movie (as William Walton and Ralph Vaughan Williams did regularly, and the English establishment didn’t seem to mind, unlike American critics who routinely looked down their nose at “commercial” music).

Sunday afternoon, Britell noted the rarity of this music being performed outside its original cinematic contexts and minus any visual accompaniment. The cheers that went up when the pianist-composer launched into an encore of his music for “Succession” were proof of the popularity of this music as played on its own.

Half of his program choices were recent movie music by other composers: Mica Levi’s eerie string figures for “Jackie,” Gary Yershon’s oddball theme for “Mr. Turner,” Jonny Greenwood’s dramatic score for “There Will Be Blood,” Kathryn Bostic’s bluesy colors for “Toni Morrison: The Pieces That I Am” and Terence Blanchard’s dirge-with-dignity for “Malcolm X.”

Britell’s versatility was showcased with a fugue for “Vice,” his lyrical score for “The Underground Railroad,” a lovely cello piece from “If Beale Street Could Talk” and the raucous big-band jazz for Adam McKay’s upcoming satire “Don’t Look Up.” (One wonders how often a toy piano, a fun element of Britell’s latest score, has been heard on the stage at Disney Hall.)

But it was his classically styled, Emmy-winning theme for “Succession” that brought the audience to its feet, managing the most sustained audience applause over the entire weekend of film (and, in this case, TV) music.

Saturday night, Bowers confessed: “I never saw myself in this classical space. I felt like I didn’t belong.” The concert demonstrated otherwise, as Bowers introduced film themes by other composers; debuted a fine new concerto for French horn; and performed excerpts from four recent scores accompanied by new images and specially commissioned poetry.

Bowers opened with film music “by composers from unorthodox backgrounds… from outside the industry,” he explained during a pre-concert talk. So Arcade Fire music from “Her,” a Shigeru Umebayashi track from “In the Mood for Love,” Ryuichi Sakamoto themes from “Merry Christmas, Mr. Lawrence” and “The Sheltering Sky,” a Bjork song from “Dancer in the Dark,” Jon Brion cues from “Eternal Sunshine of the Spotless Mind” and Jason Moran’s theme from “Selma” graced the first 20 minutes of the concert, with Bowers doing jazz improvisations at the piano on some.

The horn concerto, commissioned by the L.A. Philharmonic, was the highlight of the first half. Philharmonic principal horn Andrew Bain shone during the five-movement, 20-minute work. Adding visual interest was a series of black-and-white images, projected on a screen above the stage, that hinted at an untold story (invented by the composer) involving a forest, a foraging deer and a raging fire, possibly inside a hunting lodge or maybe in the forest itself.

The second half consisted entirely of Bowers’ own music, arranged in suites, for the movies “Green Book” and “King Richard,” the miniseries “When They See Us” and the series “Bridgerton.”

The twist was that the music wasn’t presented in the traditional manner. Instead, Bowers’ wife, “General Hospital” actress Briana Nicole Henry, created short films, and added new poetry (by Yrsa Daley-Ward, read by “Green Book” actor Mahershala Ali, “When They See Us” director Ava DuVernay, and Henry herself), to accompany the music. It proved sensory overload at times, as there was a lot to take in, but it was a reminder that most film music is accompaniment and rarely the central focus.

The most adventurous programming was Friday night’s series opener, with Guðnadóttir doubling as curator and host. Seeking, in her words, “a listening feast, from delicate melodies to really raw, animalistic textures,” she provided an evening of surprising sonorities and challenging musical material.

She opened on an unexpectedly dramatic note, as her minimalist “Under Takes Over” was played at first in total darkness, then with sections of the orchestra partially lit. “Listening in darkness heightens the way we listen,” she explained to the audience afterwards.

A startling 10-minute piece for solo triangle (“Silver Streetcar” by American composer Alvin Lucier, a champion of experimental music) was followed by two intense pieces for strings: “Nymphea Reflection” by Finnish composer Kaija Saariaho and a cue from Mica Levi’s “Under the Skin.”

In addition to music by classical favorites Henryk Górecki (a movement from his Symphony No. 4), Arvo Pärt (“Fratres”) and Gyorgi Ligeti (“Atmospheres,” familiar from “2001: A Space Odyssey”), the orchestra performed two more pieces by Guðnadóttir: 13 minutes from the video game “Battlefield 2042,” dominated by angry, often dissonant industrial sounds; and the melancholy “Bathroom Dance” from her Oscar-winning score for “Joker.”

British conductor Hugh Brunt conducted the Friday and Sunday concerts at Disney Hall, while American Anthony Parnther conducted on Saturday.