Daniel Pemberton’s score for Aaron Sorkin’s “Being the Ricardos” is unlike anything he’s written to date — a surprising choice for this think-outside-the-box composer, but one that would fit comfortably in the 1950s milieu of the film itself.

“I felt it needed a kind of classic score that echoed the golden age of Hollywood,” Pemberton says from his London studio. “A lot of the story is, in some ways, this dream of a perfect world, which Lucy’s searching for… the perfect home, a husband who is there.”

He continues: “There is an element of nostalgia, not just looking back at these classic characters, but also a time when the identity of the country was quite different. I wanted to capture some of the wonder and the magic of that time period.”

So Pemberton (a best song Oscar nominee for Sorkin’s last film, “The Trial of the Chicago 7”) wrote music for a 70-piece orchestra evocative of the era, and based primarily on a single theme, “with a bittersweet melancholia to it, but also an element of aspiration and dream.”

“A big overarching theme has become relatively unfashionable,” Pemberton says, referring to the fact that many contemporary directors shy away from strong melodies and big orchestras. “I felt this was a beautiful canvas to reintroduce that idea.”

He wrote the theme just a few days after attending the Oscars this past April. He was staying at a friend’s house in Malibu, but soon flew home and never met personally with Sorkin because of pandemic restrictions in both the U.S. and UK.

Instead, they conferred via video calls and email throughout the summer, as Pemberton toiled on what eventually became more than 65 minutes of music for the story of Lucille Ball and Desi Arnaz battling bad press, relationship issues and troublesome network executives, all while continuing to produce TV’s popular “I Love Lucy.”

The English composer didn’t know much about these actors or the iconic sitcom. “It’s not in your cultural DNA in the same way it might if you’ve grown up in America,” he says. He watched some episodes on YouTube; “for me, the show seemed to represent what was great about America, and how America saw itself,” he adds.

Pemberton also incorporated rhythmic ideas, some of them including conga drums, but avoided any replication of the Arnaz nightclub sound or invoking the vaguely Latin “I Love Lucy” theme, leaving that to American source-music specialist Michael Andrew.

“I wanted to find a different way to represent the energy of that world, the writers, the pace, the tension of the show,” Pemberton says.

His biggest challenge turned out to be the flashback sequences. “It took a long time to get that tone right,” he says, as Sorkin didn’t want to play any of that for laughs or nostalgia. “We have to see Lucy thinking, working things out, letting the audience understand the process she goes through. I re-scored that scene about 20 times.”

For the nightclub scenes and the re-creation of Eliot Daniel’s classic “I Love Lucy” theme, music supervisor Mary Ramos turned to Orlando-based big-band specialist Michael Andrew.

“There was a magic sound to Desi Arnaz’s orchestra. The goal was to get the sound of that orchestra, not a recording of it,” Andrew says. “We had to create it from scratch.” So for classic Arnaz numbers like “Cuban Pete” and “Babalu,” as well as the TV theme, he recruited two fellow arrangers to listen closely to the TV versions “and make sure we had the instrumentation exactly right, the orchestrations, voicings, every line making sense.”

And Ramos found longtime Santana conga player Walfredo Reyes Jr., who worked with Javier Bardem on playing the congas for those scenes. “Javier really channeled that energy and intensity into his performance as Desi,” she says.