The composer’s work can also be heard on the upcoming season of “Black Mirror.”

[Editor’s Note: The following contains spoilers for “Fleabag” Season 2.]

Isobel Waller-Bridge had already given “Fleabag” its provocative, signature sound with a metal-inspired theme song for its first season, but for the Amazon show’s second season, she found religion. Sort of. The composer created a score of spiritual choral music that included a naughty “Fleabag” spin to it.

Created by, written by, and starring her sister Phoebe Waller-Bridge, “Fleabag” Season 2 pits its title protagonist against God when she suddenly fancies a priest (Andrew Scott), who is devoted to his calling despite his attraction to her. In conceiving the sound for this season, Isobel Waller-Bridge felt that the religious theme should serve as the inspiration.

“Musically, it definitely didn’t feel like it needed your kind of conventional score, as it were. Then because of the church theme throughout it, we thought how about we try something that is vocal and comes from a sacred place,” said Waller-Bridge. “I am sort of familiar with vocal music. I’ve written a bit before but nothing quite like this, really.”

She adjusted the music to reflect the various stages that Fleabag goes through this season, beginning with her first meeting with the Priest, realizing her interest in him, and ultimately, becoming intimate with him.

“There’s a lot of brain power and thinking time that we spent really watching and re-watching and re-watching scenes and wondering what the sound should be,” she said. “Finding the tone of it was challenging. I went away and just wrote lots of it just to see. Then when we started putting it to the picture, it just made sense to us.”

Waller-Bridge used the silences as well as the power of the music to build the tension and drama in each scene. “Because it’s a physical comedy and in the writing, there’s not a beat that is misplaced, the silence is as much part of the score really,” she said. We wanted to use it quite sparingly because it just needed to have the right kind of impact every single time. Because sometimes it’s very, very dramatic and it needs to be.”

Amazon

“Sometimes it’s a little bit slower and lyrical, such as in the bit when we first meet the Priest and Fleabag goes home and start Googling what is celibacy, basically,” she added. “That really needed to be not dramatic, just something that actually felt quite reverent to the church and to him because we were trying to bring everyone in because [the scene’s drama] is in her head. It was still a titillating thing at the beginning, so it couldn’t be a fully formed emotion. It was more of an intrigue I think.”

Fleabag’s emotional journey is also reflected in the maturity of the voices singing in each stage of the season. She recorded with two groups of singer: a boys’ choir consisting of 12 vocalists and an adult six-piece choir.

“There was the adult singers, which I recorded first. And when we put that on the first episode, it didn’t really work, because I realized the voices were too mature,” she said. “We had just been introduced to the second [season]. There had been a bit of time passed. It was too much of a leap. Then I was like, well how about we make them a boys’ choir, a children’s choir, so there’s a naive sound to it. So we’re not going into it kind of all guns blazing with mature vocals. So then we had the boys’ choir at the beginning and then as the series developed, so that by the time we get to the end, it’s all adults.”

The original recording that was too mature-sounding became the kyrie, the piece of music that plays during the climax of Episode 5, when Fleabag and the Priest kiss and resolve to have sex. Take a listen:

“When I read the script and then saw in particular that first episode, it just seemed to really Greek in scale — the family, the big values, the things that we were starting to learn, and new people coming in,” she said. “That’s why the Greek lyrics really made sense to us.”

Kyrie is the common name of an important Christian prayer and literally translates to “lord, have mercy” from Greek. The lyrics of a traditional kyrie also served as a jumping-off point for the songs that can be heard in “Fleabag” and were supplemented with other Greek and Latin phrases.

“The lyrics to the kyrie are ‘Our Lord have mercy,’ which made so much sense on so many levels. It’s about forgiveness and repenting and growing. Then there was a bit of Christo — Christ have mercy — which is a bit more specific to, um, the Priest character,” said Waller-Bridge.

“There had to be other lyrics, and I chose, ‘nos venit,’ which basically means ‘we’re coming, we’re coming.’ It meant they’re moving towards each other in terms of Fleabag and the Priest or the family are kind of coming together or individually Fleabag is figuring out her character. There’s something on the horizon that this is coming,” she said, adding. “Then of course that can be interpreted in another way as well, in a sort of double entendre way.”

Those are not the only hidden meanings in the lyrics. Director Harry Bradbeer said, “Iso wrote the lyrics for it. But all the words are basically Latin or Greek words for private parts of the body, repeated at various intervals. They’re basically saying, ‘Cock, cunt, arse.’ So there’s a little detail that not everybody knows.”

Waller-Bridge fessed up to getting cheeky with the lyrics. “There are the occasional words that could be interpreted as filthy words. I think maybe once, maybe twice, we’ve got one of the female body parts,” she said. “We sort of snuck them in but not throughout the whole score. They’re really buried so they’re really layered deliberately under, so you really have to pick them out. But they are specifically the adults that really sing that as [Fleabag and the Priest] are developing in their way, which is fun.”

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Fans have heard other hidden meanings in the lyrics as well, which Waller-Bridge denies including, but is happy to accept.

“Some people thought they could hear ‘Fleabag’ and ‘Priest,’ which aren’t written in at all, but that was such a lovely thing because it just meant the music was really connecting to the characters from an audience point of view,” she said. “The music really was becoming the voices of their self-conscious, the voices of their energy.”

Writing “Fleabag’s” choral style of music was an intriguing challenge and offered another means of expression to add to Waller-Bridge’s repertoire. In the past she had worked with more string sections and gentler melodies, and she’s also done the scores for “Vanity Fair” and “The ABC Murders.”

“I’m just doing a solo record at the moment and that’s really my next big project. Having just literally come off writing vocal music, I want to go further with that and in a musical, character-y way,” she said. “Because that’s the really wonderful thing is when you get to do writing in lots of different genres, you get to really experiment and test out what you’re really loving. And as you evolve as a person those things evolve too.”

Waller-Bridge also landed another TV composing gig that challenged her in a different way. She scored the upcoming “Black Mirror” episode titled “Rachel, Jack and Ashley Too,” starring Miley Cyrus.

“That was really exciting to do, and working with that team and Charlie Brooker was amazing,” she said. “It’s kind of guitar with a modern contemporary sound. It’s more innovative. That sort of creepy, sort of tilted music is right up my street as well.”

Dan Wooller/REX/Shutterstock

”Fleabag” Seasons 1 and 2 are currently streaming on Amazon Prime. The new season of “Black Mirror” will be released on June 5 on Netflix.

Additional reporting by Chris O’Falt.

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