Stepping in to replace another composer on a film is never an easy task, but for Christophe Beck, coming in at the tail end of “Edge of Tomorrow” had one great advantage: the movie was largely completed.

When “Tomorrow,” which opens today, started shooting, there was no finished script: director Doug Liman and star Tom Cruise continued to craft the film as shooting went along. Liman replaced original composer Ramin Djawadi with Beck, who was best known for scoring films like the three “Hangover” movies, “Muppets Most Wanted,” “Pitch Perfect” and “Crazy, Stupid, Love.”
He jokes that getting thrown into the summer blockbuster made him feel a little bit like Cruise’s character, who is thrust into the front lines of a war with no combat experience. “You sort of get dropped in to the situation kind of running, kind of like the Tom Cruise character,” he says.  (Typically, even the original composer isn’t brought in until shooting is near complete, although some directors bring in composers earlier in the process, especially if they have an ongoing relationship).

Even though Beck has composed for thrillers like “Runner Runner,”  “Tomorrow” is his first big action pic, but that doesn’t mean he wasn’t ready. “I had a lot of training,” who graduated from Yale with a music degree before attending USC’s Film Scoring program. “I’m always entertaining possibilities and ideas even if it’s not the project I’m working on,” he says. “If I see a cool sci-fi movie with a cool score, I think what would I do there? It’s not like, ‘I’ll be starting this big sci-fi movie in a month and I need to ramp up’.”

Having said that, he knew he was coming into a situation where not only the first composer had been let go, but that Liman was figuring out  how to navigate working with a composer other than his frequent collaborator John Powell, who has decided to take a break from scoring to work on other projects.

“I think any composer going in to that situation might have met the same fate [as Djawadi],” he says. “I wonder if I had been the first composer if I would have lasted the whole time.”

Beck and Liman found their footing, but it took some time: “It took me awhile to get some stuff out of my system,” Beck says. “Doug really pushed me to constantly find unconventional ways to score scenes. That took a couple of months.”

For example, there’s an extended scene where Cruise, in the “Groundhog Day”-like plot, keeps reliving the beach invasion scene, but each time before he dies, he comes back with a little extra knowledge. “At first, we were hung up on the super soldier aspect and had a heroic theme with french horns,” Beck says. “It was important to Doug that [the audience] be able to laugh at the scene. After multiple attempts at doing it [with] a more traditional hero melody, we played it more like a punk rebel and sampled bits and pieces of the orchestra and distorted them.”

 Beck calls Liman “a very enthusiastic musician —he can play a mean Billy Joel on the piano—who always knows what he wants, even if he has to hear what he doesn’t want first. As Blunt and Cruise have both also noted, Liman doesn’t sugarcoat his criticism. “When you’re in the moment and you’re hearing it from him, it can sometimes make your heart sink, but I’d much rather work with someone where you know where you stand,” Beck says. “When he’s telling you it’s the best cue or it’s a total miss and he wonders what movie you were watching, he delivers the news i the same even-keeled manner. It’s quite remarkable.”

Working on “Edge of Tomorrow” was a sharp contrast to scoring “Frozen.” Whereas Liman pushed Beck for innovation, with the Disney animated film, “there was an expectation of a traditional symphonic sound with melody, and not too much emphasis on writing something completely original,” Beck says. “The emphasis on surprising the audience is not there. For a Disney film, you have to stick to the tradition of all that came before it.” However, at the core, he adds, “you’re still storytelling through music.”

“Frozen,” which has grossed more than $1 billion in worldwide box office, has made more money than any film in Disney Animation’s history.  “It’s always fun to have a giant hit,” Beck says of working on a movie that belongs in the pantheon of Disney’s classic films. “It’s nice to be able to tell someone I worked on a film that’s so wildly beloved and widely known so I don’t have to explain that I worked on a movie that opened three months ago and is gone.”

Beck names John Williams as his all-time favorite composer, also tips his hat to legendary Jerry Goldsmith: “He was one of my teachers at USC. He only taught one year or so and I had him. He was a huge influence on me, mainly through his ability to make such great music out of so few ideas. He was very economical. His music has a real feeling of cohesiveness. It’s almost Beethoven-esque.

His favorite contemporary composer is Alexandre Desplat. “No matter what style he does, there’s still his stamp on it it, which is a certain sophistication and minimalism,” Beck says. “It has a real elegance to it, even when he’s doing ‘Godzilla’ with 18 trombone players.”

Beck hints that he has some future animated projects in the works that he can’t announce yet. In the meantime, he’s working on the score for “Hot Tube Time Machine 2.” “They go into the future this time as opposed to the past, so the score takes a turn. It’s very cool.”