Given everything that generally goes on in a Rob Simonsen score, it’s not surprising to learn how much beyond finding the right notes actually goes into one.

“I’ve always had a lot of imagery going on in my head when I listen to music, so when the idea of scoring films as a career dawned on me, it seemed very natural,” says Simonsen. “I love storytelling – I read books about storytelling and I’ve gone to seminars about storytelling and screenwriting and it’s something that I think about a lot, so to contribute to storytelling with music to me is a dream job. It also was a good fit because I think I have trouble finishing things, so having deadlines was really wonderful because it gave me no choice but to finish.”

It’s hard to think of Simonsen’s work as ever being incomplete, already a burgeoning master of creating cohesive and vast sonic landscapes that can sustain television series for hundreds of episodes and build worlds for films that give a foundation for what the characters see inside them, whether it’s the steadily mounting pressure Gary Hart felt in his doomed presidential campaign in “The Front Runner,” perfectly encapsulates by an inspired drumline score, or the pulsating, synth-heavy soundtrack he created for “Nerve,” where like the leads, it was easy to lose track of reality when the beat was so seductive.

The composer may have just authored his most impressive work to date with “Fast Color,” where true to the title of Julia Hart’s galvanizing, multigenerational portrait of superheroes, Simonsen creates a sonic spectrum as vibrant and grand in scope as a rainbow while being mighty enough to punch a hole in the sky, beautifully articulating the inextricable yet strained bonds between Ruth (Gugu Mbatha-Raw) and her daughter Lyla (Saniyya Sidney), who she left with her mother Bo (Lorraine Toussaint) while she came to grips with her special abilities. With the push-pull of the future and the past conveyed in a mix of classical and electronic music while also finely reflecting the organic roots of supernatural power, Simonsen’s work packs a punch as much as any character onscreen and contributes greatly to the heights that the film soars to.

Recently, the composer took a break from his busy schedule to talk about his music for “Fast Color” and his ongoing collaboration with Hart, dating back to her directorial debut “Miss Stevens,” as well as getting more opportunities to work in his favorite genre.

I know the relationship with Julia goes back to “Miss Stevens.” How did you two come to collaborate?

I met [Julia’s] husband Jordan at Sundance many years ago and he and I became friends and had always talked about finding a project to work on together. Then when he and Julia started making movies, I was brought onboard and it was a great fit. She’s very sensitive musically, which I love, because it’s very much a collaboration, so we can both be musically sensitive together and it’s a very good communication process [where we can] help inform each other of storybeats and musical beats.

One of the biggest difficulties in film scoring is creating an understanding between a composer and a director because words start to fail us as a language. They can mean so many different things. They’re so subjective, so when you start creating a shorthand with [a filmmaker], you start creating an understanding for what they’re saying and what they mean when they say that, that’s when I think the rubber really hits the road. [Julia] speaks to me emotionally and tells me things that she likes and doesn’t like and we startworking early on in films to get themes based from a script or once she starts shooting. We had a lot of fun doing “Miss Stevens” and we just keep working together. I’m in process on their new one right now.

When they tell you they’re making a superhero movie with “Fast Color,” does anything immediately come to mind?

We talked about trying to do something different and we knew that it was a superhero story, but that it also had a lot of focus on the interpersonal drama between the three generations of women in the film. We just wanted to go for something grand and we knew we wanted to do a hybrid thing, which are my favorite to do – we started out more orchestral and then started leaning more towards synths in the process, which is something I love. It felt like piano was a good fit for the emotional beats and the storyline between mothers and daughters, speaking to the intimacy of the relationships [since] it’s very much about these three women, but then clearly they have the power to change the world and the orchestra seemed like a great choice to expand the canvas.

For the cues where we’re seeing them flex their powers, we’re sometimes using synths to help provide some energy and interest, but also a lot of solo violin and relying on a string orchestra. The notion of the solo violin can be very raw and has an edge to it and it sounds great when it’s played fast – or slow [laughs] – but there’s an exhilaration and with Ruth, the main character being on the run, it felt like she needed a voice, so we used that. It felt appropriately elegant.

With all of those tonalities going on, when you get to a big crescendo where they intermingle and compliment each other, do you have to think about the end before the beginning?

We worked on that once we got there. That was one of the last cues that we did and the rest of the score was in a good place, but we knew that we had these big crescendos that needed to be tackled. It was a very big moment with a lot of score that needed to sustain a longer set-piece and I just shut the door on the studio and I didn’t come out until I had the monkey by the tail. Then Julia came in and I played it for her and she loved it, but we worked very hard on nailing that whole sequence and getting everything right.

Is it fun to go big? With both this and “Captive State” recently, you’ve really gotten to create these worlds with the music.

It’s great. I love films that have grounded drama but are taking place in fantastical worlds or [have] a surreal quality to them. These are the films I’m most interested in, so I’ve been waiting for opportunities to have canvases like this where you can blow things out a little bit more and be a little bit more bold or daring or aggressive. Not that I have any problems scoring films that are smaller, intimate stories, but I get really excited when we’re in a world where the rules of reality are different.

Your score for “Nerve” really seems like an eye-opener in that regard. Did you feel like it opened doors for you to do that?

Yeah, I think “Captive State” came about because the music editor was the music editor from “Nerve” and he had actually been friends with Rupert Wyatt since college, so he proposed some of my music to Rupert and he responded really well and we met and worked on that film and it was a really great process. Rupert gave me a lot of freedom and wanted something different, so “Nerve” was a bit of a departure point and the directors of “Nerve” are good friends of mine and have been for years, so it’s interesting how some of these opportunities come about. I know the music that I listen to and the music I want to create, but I don’t know that other people necessarily know that, so it’s a little bit of serendipity that I got “Nerve,” and I certainly think it’s opened up some doors and hopefully “Fast Color” and “Captive State” will open up more doors – sci-fi is my favorite genre, so I hope to get to do more.

“Fast Color” is now open in limited release. A full list of theaters is here.