For the past month, "Captain Phillips" has riveted filmgoers and critics with its uber-realistic take on piracy and hostage-taking. One might expect a film with such a harrowing story and epic scope would have a similarly dramatic score. But the work of composer Henry Jackman, though extremely complementary to what was seen on screen, ended up being far from the theme-heavy bombastic music that is frequently on display in such epics.

Jackman found his principal challenge was making the music objective but also interesting from a story-telling perspective. "In a movie like ‘Captain Phillips’ there is musical constraint, having a profound respect for what it is that’s on screen," he says.

This, of course, was largely due to the involvement of director Paul Greengrass. "He’s a journalist and if you think about the background of directors in general, you get guys coming from editing or effects or TV," Jackman says. "Paul’s avid interest in global politics and his background as a journalist affects his work…he is therefore enormously scrupulous."

Greengrass wanted to approach the story both objectively and skeptically. The director is "very wary of some of the devices of traditional scoring that you would expect to find in a classic, narrative blockbuster," Jackman says. "Information-based music with heroic themes or music telling you that ‘this is a bad guy’ is an absolute no-go for Paul. It would be very easy for ‘Captain Phillips’ to feel like ‘American in distress’ and Somalis as ‘clear bad guys.’ There is a little bit of that, and if you want to read it as a patriotic saving of an American in distress, you’ve got that. But the music shouldn’t tell you that."

How did this affect his approach to the film as a whole? According to Jackman, he ended up developing a musical style which very deliberately is not lyrical or melodic or theme-driven. "It took a while to get there," he says. "I write a lot of different music and if you do an animated score, you need to do that and here we needed to put all of that to one side and with the smallest amount of musical information."

Citing an example, Jackman speaks about when the USS Bainbridge shows up for the first time. "You think, ‘Thank God…something’s happening!’" Greengrass, however, was enormously concerned that that critical part of the film did not get affected by a "heroic" theme. "To him, the navy showing up was an inevitable part of story," Jackman says. "His unique way of filmmaking informed the score. In a funny way, I had to take a backseat to the acting…You mustn’t overstate yourself in a way that you’d be expected to in a film like 'Harry Potter.'"

Jackman found this approach to filmmaking to be uniquely challenging, but goes out of his way to say that Greengrass would never be dictatorial. The director would invite invite his composer to be as skeptical as possible. Jackman accepts this was to a large extent a necessary process because the film is an unbearably tense thriller, with one long arc from when pirates breach the Alabama until the climax.

But nevertheless, it was particularly tempting for Jackman to foreshadow what was to come when the Alabama first set sail. "We all know everything isn’t going to be cool," he says. "This is the only time when everything is under control. The first version I wrote I thought was pretty neutral but it still had some element of ‘this is a big movie – it’s not a TV show.’ Paul said ‘it just feels a little unobjective...I feel I’m being told a bit too much.’ He just picked up on it."

Jackman saw the realism that Greengrass had attempted to create in the finished product. Like virtually everyone else, he praises the film’s finale. "In a less realistic movie, the sense of ‘being rescued’ would be more simplistic, with relief, and a ‘yay’ feeling. This was unbelievably realistic. When the concept of the film is that credible and performance that strong, it’s appropriate for music not to take such a large scale."

This is not to say the music was not tremendously important. "There’s story-telling in there but you have to find more subtle ways," Jackman explains. "You work harder with individual sounds and textures where you can find sound that uniquely feels dark or tense. There isn’t as many expected elements as you’d find in a more traditional score. You spend longer in production."

How did this work in practice? "We could spend ages morphing sounds and treating them," Jackman says. "We made sounds from a cello that are the last thing you’d expect from a cello – gnarly, squirrelly, unsettling sounds."

He also avoided a favorite of many composers – "ethnic music." Nothing would offend Greengrass more than the use of ethnic Somali music in the film, Jackman says. "Captain Phillips and Muse are both captains," he continues. "Muse is not a ‘devilish’ character. These are two captains and if Phillips had been born in Somalia and Muse in America, it would just be the other way around. It was important not to smother Somalis in ethnic music."

In the result, Jackman thinks he "gained an appreciation of the nth degree of minimalism. It was much more about tone and texture and color and delivering feelings of uncomfortableness. When Paul objected and said ‘it has too much information in it’, I’d find another level of deconstruction. I was fascinated by his concept of skepticism."

As for his role in the film coming together, Jackman notes he would never have the "temerity" to suggest to Greengrass what to put on the screen. Though he didn’t see a cut until relatively late in the game, that didn’t affect his approach. "Even if I had known about it years before, I don’t think it would be appropriate," he says. "I would even argue it was kind of a luxury because when I saw the film, it probably represented 90 percent of what they wanted to achieve. That’s a bonus from ‘it’s a first cut’...already a spectacular realization of what they wanted to do." ("They" in this context represents Greengrass and film editor Chris Rouse, whose collaboration Jackman describes as "an awesome duo of intellectual and professional capability.")

All of this light having been shed, to Jackman, the music is absolutely not a secondary element. "But it has a uniquely disciplined role to not affect what’s going to go on where you’re asked to write a theme first," he says. "I found it extremely inspiring upon the first viewing."