Dear Linda Cohen,

Selecting music for a film isn’t that different from the casting process: you’re essentially casting a song for a particular scene, trying to find something that can capture the mood, the energy, the emotion of a moment—a piece of music that can play the part. Sometime you cast against type (think “Stuck In The Middle With You” in Reservoir Dogs). And sometimes you have to go with the most obvious choice.

Midway through Triple Frontier, we find our heroes – five ex-military pals reunited for one last covert mission – driving through the jungles of Mexico, headed for a secluded villa where untold millions of dollars (and some gun-toting drug dealers) await them. The song playing over this scene is Creedence Clearwater Revival’s “Run Through the Jungle”—a song which literally describes what is happening onscreen. That music choice is pretty on-the-nose. Prosaic, uninspired, but, all things considered, kind of effective. Which makes sense, since Triple Frontier is exactly that kind of movie: on-the-nose, prosaic, uninspired—and, in the end, kind of effective.

Your other music choices throughout Triple Frontier are uneven. There are a few other cues that feel a little too conspicuous: Metallica’s “For Whom The Bell Tolls” shredding over the opening sequence of military choppers descending upon their prey; Bob Dylan’s “Masters of War” (just in case you weren’t fully convinced that these five men are, yes, masters of war!). And there are a few weird ones, too: I’m thinking of that wistful Fleetwood Mac tune playing over the scene of tattooed miscreants gathering for an amateur MMA fight (if there’s one thing that doesn’t conjure the vibe of a bloody bare-knuckle brawl in a high school gymnasium, it’s Lindsey Buckingham’s falsetto).

Likewise, the cast of Triple Frontier has its winners and losers. I was glad to see Charlie Hunnam and Garrett Hedlund on screen together, if only so I can finally be 100-percent sure they’re two different human beings. Pedro Pascal is quite good in the role of the coked-out pilot who, if this film had been made in the 1970s, would have been played by John Cazale. And Oscar Isaac continues to rise to the level of the material he’s given without ever surpassing it.

And then there’s Ben Affleck. He shows up about twenty minutes into the film, a failed real-estate agent in pleated khakis and grandpa sneakers, looking as tired and forlorn as he does on press junkets for superhero movies. And he instantly owns the movie. The thinness of all the characters we’ve been following to that point is, in the moment Affleck appears, blindingly apparent.

Affleck’s career has been an interesting one. It’s easy to forget that his first big success was winning an Oscar, and that he spent the following decade-and-a-half as an action star and romantic lead (and perpetual tabloid whipping boy) before winning more awards, including another Oscar. Yet no one thinks of him as being particularly talented as an actor. He isn’t as twitchy as Brad Pitt or as ruminative as Matthew McConaughey. He’s not as controlled as Michael Fassbender or Christian Bale. Even his pal Matt Damon is better known for his everyman magnetism. Affleck is just…profoundly normal. So is his character in Triple Frontier. Yet even as the screenplay pushes him closer and closer to the role of antagonist, he’s still the one you’re hoping will make it out alive. Forget those other

Thematically, Triple Frontier goes to some interesting places. Or perhaps it ends up in some interesting places totally by accident. What begins as a traditional story about good men succumbing to avarice eventually becomes a story about bad men trying to mitigate their badness. But their decision to resist shedding more blood is preceded by so much thoughtless bloodshed that it’s hard to buy the turn. The only thing that makes it feel like more than just a plot convenience is Ben Affleck. And that’s true of so much else in this movie. There is melancholy, and humour, and suspense, and in mostly comes from him.

“Run Through The Jungle” is a rare hit song that never once changes key. It sounds like it does, but it doesn’t. And sometimes great music is defined by the things it doesn’t do. Same with acting. You might think that Ben Affleck has been playing the same note throughout his career. And maybe he has. But that doesn’t mean he isn’t one of the greats. And he proves it by making Triple Frontier feel deeper and more thoughtful than it would have been without him.