A compelling hot-button subject and engrossing “true story” runs up against a ponderous script, pedestrian direction and the limited range of star Jim Caviezel in “Sound of Freedom,” a lumbering thriller about international child sex trafficking that flatlines when it’s meant to be moving, uplifting and inspiring.

If you can’t make a weeper out of a helpless, mostly Third World kids being lured away from their parents and snatched for online porn and prostitution to an audience that lines up to see every movie from the star of “The Passion of the Christ,” maybe you should watch some of the other films on this subject and see what you’re getting wrong.

Director Alejandro Montverde, who broke out in the faith-based corner of filmdom with his anti-abortion drama “Bella,” and Caviezel tell us the story of Homeland Security agent turned abducted child rescuer Tim Ballard, a veteran hunter of online “pedos” who has an abrupt, emotionally-lacking and dramatically-flat “conversion” from a guy who catches the “customers” in this heinous trade to a man who wants to save kids because “God’s children are not for sale.”

A colleague only has to mention how their work is seeing what a “sick world” this is a couple of times for Ballard to suddenly get up from his work computer, saunter (not storm) down to the most understaffed Homeland Security jail in America and cozy up to his latest bust, an ideologue who writes books about perverts’ insatiable lust for children, convince him he’s “one of us” and use the prisoner’s expertise to break into a Colombian child kidnapping ring.

Just like that, and with a single tear, shot in close-up, all that we get out of man-manikin Caviezel.

Tim makes his way to Colombia, working his way towards the “model” (Yessica Borroto Perryman) who recruits kids by convincing their Honduran (etc.) parents that “They should be in the entertainment business” (some scenes are in Spanish with subtitles) and the high roller Jeffrey Epstein types (unseen) who back this soulless recruiter.

Along the way, he links up with a Colombian cop (Javier Godino) who puts him in touch with a “cartel” veteran and ex-con who has experienced some sort of late-life conversion so that he’s saving kids his own way. The great character actor Bill Camp (“Birdman,” “Joker”) makes little attempt to go “Latin” here, feigning an accent for roughly half a scene, letting his Panama hat, Hawaian shirt and omnipresent cigar establish his Colombian cartel bonafides.

Tim, who takes on the name Spanish version of the name, “Timoteo,” will try to hunt down and free two Honduran kids who we see snatched thanks to their gullible father’s compliance in the opening sequence, setting up a Cartegena sting and even plunging into the “rebel” packed jungles to fulfill his personal mission.

We also see Tim’s big family and home life, with Oscar winner Mira Sorvino here to weep or be on the verge of tears in every appearance. Kurt Fuller plays the overly-sympathetic Homeland Security boss who doesn’t do much to corral this agent who’s “going rogue.”

“We’re Homeland Security! We can’t go rescuing Honduran kids in Colombia!”

And we’re treated to Caviezel’s attempts to smile — an unnatural act throughout his career — and show us the motivations, passions and vigilante-level fury this law enforcement office feels about this new mission he’s suddenly taken on.

The villainous characters are caritactures, but I didn’t buy virtually any of the performances. And “Sound of Freedom’s” funereal pacing and struggling manipulations left me cold, when I was expecting big emotional moments that never came. Movies like “Trade,” “The Whistleblower” and even the similar “Trade of Innocents” wrung more emotion out of this subject.

But “Sound of Freedom,” which takes its title from a children’s clapping game and our young victim (Cristal Aparicio) humming the movie’s theme song, relies on closeups of Caviezel’s inexpressive face to carry the story. It’s not enough.

Caviezel made it his business to cynically pander to this conservative religious “QAnon” friendly audience, long before he starred in TV’s “Person of Interest,” which was canceled because he’s just not an interesting, expressive actor person.

When your movie is “presold” by marketing, tagged with an appeal to “buy more tickets” to make it appear more popular than it is, you’re all but ensuring its profitability. Presold, extolling the values of a faith-based film even if this isn’t wholly confined to that genre, maybe you don’t try as hard to give it heart and get it right.

Rating: PG-13, violence, children in sexual jeopardy subject matter, profanity

Cast: Jim Caviezel, Bill Camp, Cristal Aparicio, Javier Godino, Lucás Ávila, Yessica Borroto Perryman, Kurt Fuller and Mira Sorvino.

Credits: Directed by Alejandro Montverde, scripted by Rod Barr and Alejandro Monteverde. An Angel Studios release.

Running time: 2:15